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Monsters of Monsters

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1. Be Brave.

Sans woke up with a pain in his chest and a scream lodged in his throat.

The house was silent except for the ticking of a clock, the soft whirl of the trash tornado, and the sound of rain falling on the roof. Rain. There was no rain in the Underground. The world hadn't reset. They were still above ground.

Just another nightmare.

His bones were damp, soaked in the same cold sweat as his sheets. Sans rolled to one side, curled up against the world, and counted. Inhale for four, exhale for six. Inhale for four, exhale for six. Soon the frantic beating of his soul settled. There was a flash of lightning barely visible through the window and eight seconds later the distant roll of thunder accompanying the rain. He thought about laying down, but what was the point? It wasn't like he would be able to go to sleep.

There was a good – okay, 100% chance – that Papyrus was still up. Probably on the internet or watching TV with the sound off and the subtitles on. Sans could go sit with his brother until the lingering anxiety from the nightmare left. It happened often enough that Papyrus wouldn't even comment on it. Mostly.

He pushed off the blankets and sat up in bed. A bed. What a novel concept. As far as Sans was concerned, a mattress on the floor was just as good. Getting him a bed had been his brother's idea. Papyrus had insisted that now that they were on the surface, Sans should have a bed like a real adult. It just seemed like too much effort to argue. Besides, using a bed seemed like a small thing to do if it made Papyrus happy.

It seemed weird to have to climb out of bed after so many years of just being able to roll onto the floor from the mattress. Not a bad weird. Just weird.

His feet didn't quite touch the floor when he hung them over the side. There was a height joke to be made there, but Sans cut it short. Another flash of lightening. Another roll of thunder. Sans braced himself to put his foot on the floor.

And hesitated. What if there was something under the bed?

Sans shook his head. Where had that thought come from? The only things under his bed was a couple of wrappers, an empty soda can, and some socks he couldn't be bothered to retrieve. It was a place to collect dust, trash, and clothes. That was it. There was nothing there.

His foot hit the carpet with no issue, and Sans couldn't stop the sigh of relief. Then he laughed at himself. What else had he expected to happen? Sans shuffled unenthusiastically towards the door.

He shouldn't look behind him. Something might be watching.

What the fuck? Sans froze half-way across the room. The nightmare was making him jumpy or something. Why else would he think such things? Even though every bone in his body screamed not to, Sans turned around.

There was the window. There was the bed. There was the trash tornado, the dresser, and the pile of book stacked on the floor right next to the bed. What there wasn't was anything under the bed. Just shadows where the light didn't reach.

Lightening flickered showing through the curtain, throwing the edges of the room into sharp relief. There was... nothing under the bed. Absolutely nothing.

Right. Sans definitely needed to go down and hang with Papyrus. Anything to keep his brain from thinking about things that definitely didn't exist. He turned around, and defiantly walked towards the door.

Behind him, red eyelights cut through the darkness beneath the bed. Those eyes watched Sans until the door shut behind him. Then the monster under the bed smiled.

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2. Watch a funny video.

It was only eight o'clock at night and Sans was already in bed.

He wasn't sleeping though. Sans wasn't quite tired enough yet. It was just the cheap thrill of not having to get out of bed that saw him still in it. He'd been in bed all day long, leaving only to get food and find his phone charger when the battery had dropped below five percent. This was what his life was like when Papyrus went out of town for a few days. Living on the edge.

The remains of dinner – pizza delivery, humans sometimes had the best ideas – was sitting on the floor beside the bed. It made Sans's room smell vaguely greasy. Which was comforting in its own weird way. Kind of reminded him of Grillby's. Something Sans would have gotten had Grillby's delivered.

Sans knew he'd have to put the rest of the pizza in the fridge at some point. He could eat maybe a quarter of the pizza in one sitting even if he loved it. Too much food just made him feel queasy. He never ordered pizza from the little local shop down the street when his brother was home. Papyrus said the sauce tasted too much like spicy ketchup. As far as Sans was concerned, that was a plus.

Currently, Sans was watching videos on his phone. It was another guilty pleasure. Not that he couldn't watch comedy with Papyrus around. He just had to be more... selective of his choices then. Without Papyrus around, Sans could watch all the mean comedy routines he wanted.

"Six weeks, people. Six weeks I've been waiting for them to give me access to this system. A system I need to do my job. And I find out that the only issue was that some guy in IT didn't want to sign a single piece of paper."

"After I told him what had happened, my co-worker replied 'Oh. You've met Speedbump.'"

"I was like 'Speedbump? Why do you call him Speedbump?'

"The guy looked me straight in the eye and said, 'Because the only thing he's good for is slowing everything down.'"

Sans huffed out a laugh at the joke. But something, someone, found that statement even funnier because there was a sharp bark of laughter from under the bed. He froze. That hadn't actually happened... had it?

Before he could think about it and freak out, Sans was scrambling off the bed. He dropped down beside it. Underneath the bed was just shadows. Too many shadows. Was there something there in the darkness?

Nope. Not going to play at that. Sans got back up, teleported to the bathroom, grabbed the flashlight that Papyrus always kept in the top drawer, and teleported back. This time he turned the flashlight on and shined it up under the bed. The shadows disappeared.

Nothing. Well, nothing unexpected. Socks, a pair of shorts, two monster candy wrappers, and a lone soda can that had rolled towards the foot of the bed were all there.

Had the laugh been part of the video? Sans felt a bit ridiculous as he got to his feet, turning the flashlight off in the process. It took him a few minutes to find his phone among all the rucked up blankets, but Sans was eventually successful. He replayed the last minute of the video.

There was no laughter.

It didn’t make sense. None of it made sense. Sans was home alone. There was no one under the bed. And yet, he'd heard someone laugh and that sound came from under his bed.

"maybe i fell asleep." Sans hadn't, but it that seemed more likely than someone being under the bed. He put his phone down on the bedstand. Well, since he was up, he should probably put the pizza away. He'd kicked the box in his haste to look beneath the bed, and Sans walked over to it.

The lid was open. There were only two slices of pizza left in the box.

Sans slept with the flashlight on and pointed under his bed for the rest of the night.

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3. Do not give in to fear created by your imagination.

The problem... well there were a lot of problems with the situation. Sans had something living under his bed. Sometimes. Maybe. There was a possibility.

So far all Sans had was circumstantial evidence. Little things that were just... off. Stuff moved around the room. A wrapper for a candy bar swirling in the trash tornado that Sans had never eaten before. Red eyes in the dark that were there and gone when he blinked. A blanket that sometimes wound up under the bed. The heavy feeling in his soul that he wasn't alone even when no one should be in the room.

There was nothing he could point as evidence while telling his brother, or anyone really, what was going on. Papyrus would believe him. His brother was cool like that. Anyone else? Hell, half the time Sans didn't quite believe it.

Why did it only appear at night? Why was Sans so convinced that light would make it disappear and keep it from reappearing? What was with the intrusive thoughts of horror and feelings of dread that always seemed to crop up? The problem was Sans kept reacting to the situation. He needed to be a bit more proactive.

Time to apply a little science.

Light was the first experiment. His weird instincts had been right. Leave a light on and the feeling that someone else was in the room never came. Leave the light off and there was a good 50/50 chance it would show up. Sans would know. He did the math to get that statistic.

Sans didn't need to be in the room for it to appear. That was the most surprising finding. He set up a couple of tells around places that seemed to generate the most activity: his bookshelf, the blanket, his desk. The chalk lines in front of the books smeared. The red mark in the corner of the blanket was no longer visible in the morning. The tape holding one of the drawers closed separated as it was opened. It couldn't be Papyrus. Papyrus didn't go into his room. That only left one culprit.

Food was another experiment. The carrots all too casually left beside the bed were untouched. So was the salad. And the kale chips. Papyrus had asked if Sans was feeling okay after that, which was why he'd switched to leaving out some Grillby's. That was a lesson in self-restrains Sans was not willing to repeat any time soon.

The burger and fries were gone the next morning. Heck, it looked like something had licked the burger wrapper. There wasn't even a speck of grease on it. Whatever was under his bed at least had good taste. Something animal like maybe? Sans picked up the trash only to see a scrap of paper with shaky writing in bright red ink.

Next time leave mustard.

Holy shit. It could write. It understood words. Could it speak?

It was nighttime, but not too late. Sans had been drifting off to sleep when it happened. That heavy, foreboding feeling that settle in his soul was back. He wasn't alone. Something was in the room with him. Sans rolled onto his back and stared up at the ceiling.

"hey. you there?" Silence. Sans laughed a little uneasily. "seriously buddy, i know you are there. just say something."

"Whatta'ya want me to say? Fuck you."

Sans would recognize that accent anywhere. It was the languid rolling cadence and dropped syllables of the streets of Hotland. Sans had spoken that accent when he was young. Before he'd worked hard to suppress it. The voice was also deep – like his – though with a rougher, almost sub-vocal growl to it.

Holy shit. The thing under his bed was from the Underground. He was a monster.

"no need to be like that." Sans could feel his soul pounding in his chest. A monster. Why had that not occurred to him before? "take it the burger was a hit."

"You don't gotta feed me."

"you sure? you even left a request. i can get you some mustard next time."

"Just leave me alone."

"that's not going to happen, buddy."

There was no reply. Just a sudden lack of presence. Sans took a deep breath in and let it out. Fuck. A monster. He should have known better than to treat someone like a thing.

Next time, Sans would do better.

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4. Do not wake the monster under your bed.

Sans wasn't sleeping.

That seemed to be his life lately. His brain was doing the thing where it kept running around in circles, like a hamster wheel turned sideways. Sans was sorry he even got out of bed this morning ago. If he'd known he would be facing a bout of insomnia after waking up, Sans would have just kept sleeping.

He was so, so tired. And bored. But mostly tired. Sans couldn't focus on anything, which ruled out reading, or watching videos, or even thinking. Yet he was still bored.

Almost idly, Sans let his hand drift downward. His finger bones idly traced the ridge of his iliac crest where his shorts clung. He wasn't really into it. Not yet. But it was something to do. Something to force his mind to slow down.

As Sans touched his ilium, he felt his magic give the first faint stir of interest. Sans closed his eyes and sighed. He didn't even know if this would go anywhere. Sometimes it led to release and sometimes he got half-way through before his body decided sleep was more important that getting off. This might be the latter. His magic was certainly slow to respond.

So Sans touched himself, letting it build. Then he'd decide that it wasn't going anywhere, turn over, and settle down to sleep. Only to decide that maybe coming was more important. He'd turn back over, trail his hand back down, and continue touching himself. He had no idea how many times he went back and forth. Time didn't seem important.

Each time his magic burned a little hotter and the pressure in his pelvis grew a little heavier. Sans could feel his breathing speed up. Magic gathered in his joints. It felt good in a lazy, heated way.

Nothing had formed yet. He wasn't that far along, and Sans kind of wanted to hold off. There was pleasure in holding back until it bordered on too much. Sans was enjoying it. Tracing the holes in his ischium left him gasping. Soon now.

*thump* *thump* *thump*

Sans froze, his hand still down his pants, and the heat of magic throbbing in his pelvis. He'd felt that. That had come from under the bed. Like someone pounding on the ceiling of some noisy neighbors to tell them to keep it down.

No. Absolutely not. It was his room and his bed. He was allowed to masturbate in his own damn bed. The knowledge that there was something - someone - under his bed listening to him was not helping with the whole getting off portion of the evening. His soul pulsed uneasily.

"i know you're there. do me a favor and just not listen for five minutes," Sans hissed. Almost immediately, the monster under the bed spoke.

"Five minutes? Seems like your sellin' yourself short."

That... was not a joke about height.

"i'll have you know no one has ever complained about getting the short end of the dick with me," Sans replied.

"I don't know. That statement seems a bit premature." Sans snorted. Okay, that was a good one. "I ain't saying your size is the problem. Just your technique."

"sorry, i don't take criticism."

"Do you need some pointers?" There was some shuffling, like the monster was getting comfortable. "I'm awake now. Might as well give some advice. It's my one good deed for the year."

"yeah, you're a real boy scout." Sans had to preen a little at the sharp bark of laughter. His good feeling lasted until the other monster spoke again.

"Roleplaying is advanced shit. You can't even use your hand to get off."

"i don't need your help," Sans replied. Then he dropped his voice, because he did not want to have to explain to Papyrus what he'd been doing. "i know how the plumbing works, thanks."

"You sure? 'Cause it sounds like the pipe is clogged. If you can even find the pipe."

"oh fuck you."

"Promises, promises." The words were higher pitched and sing-song. Then the voice dropped back down. "What'sa matter? Gotta case of stage fright?"

The worst part was, the monster under his bed was right. It wasn't like Sans hadn't performed for an audience before. He had. But there was big difference between doing a routine in front of an audience and getting half way through a rehearsal before realizing that someone was watching.

"can you just be quiet?"

"Nope." The monster popped the p in an incredibly annoying way. "Not if you're going to jerk off above me. I was fine sleepin' my life away and you woke me up."

"i can make you go away."

"Yep. But then you'll have'ta deal with the fact that you sexiled me." The monster's words turned baiting. "What you waiting for? Or do you want me to hear? Gotta bit of an exhibitionist streak?" Then, once again in a sing-song voice. "I know what you're doing."

That proved to be the breaking point for Sans. He reached out and turned the light beside his bed on. The monster under the bed started laughing. There was a mean edge to the sound, harsh and knowing. Sans grabbed the flashlight he now kept by on his nightstand and shined pointed it under his bed without bothering to look.

Sans could hear the monster's laughter in his ears, even as it faded away.

Nearly an hour later, Sans finally succumbed to sleep. His magic still burned in his pelvis when he finally nodded off. Which explained why he dreamed about red eyes watching him as he touched himself.

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5. Watch your ankles when you get out of bed.

In the two months since Sans had started interacting with the monster under his bed, he'd found out the other monster had exactly two moods: angry and asshole. That was it. Sans wasn't sure two moods was enough to constitute a personality. Then again, Sans really didn't have much room to talk.

The monster under his bed was there. Sans could feel the tension in the air, the oppressive feeling of dread that hung in his soul. It was kind of comforting. "i'm going to the kitchen to get some snacks. you want something?"

"No."

Ah. Tonight's mood was angry. Sullen anger, but definitely anger. "suit yourself. toriel made cookies. you not wanting anything means there is more for me."

"Hey wait."

That was all the warning Sans got. Fingers bones wrapped around the lower end of his tibia and fibia before he could dodge. It wasn't an attack. It was just the monster under his bed. It should have been fine.

Fear raced up spine, choking back his words. There was no thought. His brain was filled with the white noise of terror. Sans made some sort of noise, a high pitched squeal. He couldn't seem to catch him breath enough to scream.

Sans had three strategies for dealing with problems: passivity, empty threats, and overkill. His brain by-passed the first two and went straight for the third. The electronic whine of four blasters charging filled the air. The monster under the bed released his ankle.

It was enough to jolt Sans back into thinking as opposed to reacting. What was he doing? It was too late now. The blasters were already fully charged, the sound shifting as they got ready to fire. Sans scrambled backwards to get out of the blast zone.

There was no way Sans could reabsorb that much magic. That didn't stop him from trying. He pulled back on the blasters, hard, trying to dissipate them. It didn't work. Sans didn't even have enough time to redirect them. They fired with a blinding flash and a staticky roar that was almost deafening.

The room plunged into darkness once more. The silence that followed the attack was eerily loud. Somehow Sans managed to find the light switch for the room. With the light on, he could see the damage. The bed was in four pieces and smoldering. Twisted bits of metal and smoldering cloth marked the path the blasts had taken through the mattress. There was a scorch mark covering half the wall behind it.

Sans felt himself begin to shake. He wanted to laugh, but there was nothing funny about the situation, so he trapped the urge behind his teeth. The sound he made instead was small and hurt. He had gained no experience. His LV was still at zero. There was no dust under the wreckage that was his bed. Small mercies.

"SANS!" Footsteps pounded down the hall. Seconds later, the door to his room was thrown open hard enough that the doorknob embedded itself in the wall. Now the door was stuck open.

Papyrus looked around wildly. There were several bone attacks floating in the air above his shoulder. "WHAT IS GOING ON?"

"bad dream." That seemed like the safest explanation. Certainly better than 'A monster has been living under my bed and I accidentally tried to kill him.'

"WOWIE." Papyrus surveyed the damage. "AT LEAST NOW YOU CAN'T COMPLAIN ABOUT HAVING A BED ANYMORE. IT IS BED AND GONE. "

"good one, bro." Sans could tell he was shaking, his bones rattling faintly, but he didn't seem to be able to stop. "i guess i loved it to pieces."

Not his best pun, but it was worth the effort just to hear Papyrus scoff. "WELL. YOUR OLD MATTRESS IS STILL UP IN THE ATTIC, BUT IT'S TOO LATE TO GET IT DOWN. YOU CAN SLEEP IN MY BED TONIGHT. I WON'T BE USING IT BECAUSE I DO NOT NEED EIGHT HOURS SLEEP, BUT NOT EVERYONE IS AS GREAT AS ME. MY BED IS OPEN TO YOU. IF YOU WANT IT?"

His brother probably didn't mean for the last sentence to be a question. It hurt Sans's soul a little just how tentative Papyrus sounded. As if he could tell his brother "no" when he could give him something. "sounds great, paps."

That was all it took for Papyrus to start gently herding Sans out of his room. "TAKING CARE OF THE BED CAN WAIT TILL MORNING. LET'S GET YOU SETTLED."

The racecar bed was gone, replaced with a larger, wooden bed. An adult bed Papyrus had said. As if Sans wasn't aware that Papyrus was more of an adult than he was most days. Sans let him fuss over the blankets, the pillows, and whether to leave a nightlight on or not. After a good fifteen minutes Papyrus turned out the lights and closed the door. Sans was alone.

Being alone was was not as comforting as it once was. Sans stared up at the ceiling. He doubted he'd sleep the rest of the night, despite the fact the house had gone dark and quiet again. His thoughts kept coming back to one realization. Those were not fleshy fingers that had wrapped around his ankle.

How had he never realized the monster under his bed was a skeleton?

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6. If you feel breath on the back of your neck, something is definitely there.

Two weeks. It had been two weeks since Sans had destroyed his bed. Two weeks of silence, of the absence of pressure in his chest, and of being truly alone when his brother left the house. Sans had been pretty sure he hadn't killed the monster under his bed. With every day he was getting more... worried was a strong word that required actual emotional effort. As was concerned. Resigned worked though. Sans was good at being resigned to things. And he was slowly becoming resigned to the fact that the monster under his bed was gone.

Sans was back to sleeping in his room. He and Papyrus had gotten his old mattress down from the attic just a few days after this incident. It smelled faintly, but it was still usable. That was an attitude leftover from the Underground. Don't throw anything away until it was useless. You never knew when you might need it again.

Right now, Sans was getting ready for bed by brushing his teeth. He hadn't bothered to turn the lights on. Papyrus had a nightlight in the bathroom in the shape of a couple of shooting stars. It provided enough light for Sans to see with, and gave everything a soft golden glow.

He was spitting into the sink when the nightlight flickered. Sans glanced at it, but the light stabilized and remained steady. Huh. Power surge. Wouldn't be the first time. At least the power didn't go out completely.

There was a small glass by the sink. Sans filled it with water, washed the last lingering taste of fake mint out of his mouth, and spit. Done. Now he could go to bed.

Except there was the faintest tickle of breath on his cervical vertebrae. Inhale cool. Exhale warm. It sent prickles of magic across his bones. Sans was suddenly hyper aware of the heavy feeling in his soul. He knew that feeling.

Sans looked up and into the mirror.

There was a monster standing right behind him.

Not any monster. A skeleton monster. A skeleton monster that looked like Sans. He would recognize that face even if his own wasn't being reflected back at him in the mirror right beside it. Sans was looking at himself. Or at least a slightly darker, slightly larger, more emo version of himself. One with a cracked eyelight, jagged teeth, a single gold tooth, and red eyelights. A monster that looked like him wearing a fur trimmed leather jacket and a dog collar.

"Hey sweetheart. Miss me?"

Sans whipped around. There was no one behind him in the bathroom. Yet he'd seen him. He'd heard him. He looked back over his shoulder. There was the other Sans grinning his shark tooth grin, standing in front of him in the mirror.

Slowly, Sans turned back around. The other him laughed.

"Nice of you to give me your back."

"if you wanted me dead, you would have killed me already." That at least seemed like a safe bet.

"Sure. Right. Whatever helps you sleep at night."

"on reflection, i might have made a few mistakes," Sans admitted. The pun did not go over the other monster's head. The grin became less sharklike and more genuine. "seeing as we're mirror images of each other."

"Not quite." The other monster reached out, putting a hand against the mirror right over his shoulder. Sans should have seen an arm out of the corner of his eye. There was nothing there. "Still both assholes though."

Sans snorted. "i'm not an asshole."

"You are most definitely an asshole. An asshole who's sleeping on a mattress on the floor."

Guilt hit Sans like an aftertaste in the back of his throat. His eyes darted to the left, still expecting to see the monster standing behind him in the mirror. "sorry about that."

His doppleganger shrugged and took back his arm. "Shoulda expected it. If anyone grabbed me like that back home I woulda reacted the same. Don't worry. It had some unexpected side effects."

"now you're trapped in a mirror."

"Ain't trapped here. Ain't trapped under the bed anymore either. 's nice."

That made Sans narrow his eyes. "what does that mean?"

"You're smart. Figure it out for yourself." The nightlight flickered again, momentarily plunging the room into darkness. When it came back on a second later, the other monster was gone. Sans felt like he could suddenly take a deep breath. He hadn't even realized he'd been breathing shallowly until that moment.

Well. That was some cryptic bullshit.

"asshole." The word sounded fond, even to Sans.

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7. The creak on the stairs means nothing.

The first thing Sans realized when he woke up was that he'd fallen asleep on the couch again. This was becoming a habit. Despite the fact that Sans had slept on his old mattress for years, it felt wrong now. Maybe he'd just gotten used to actual back support.

The second thing he realized was that there was a reason he'd woken up. Something was moving at the top of the stairs, slowly descending another stair that creaked under the added weight. Three guesses who it was, and the first two didn't count. Sans glanced up and into the darkness.

Two red eyes looked back down at him. The TV was still on, the light from it blue and flickering as an infomercial played. The other monster didn't try to come all the way down. Instead he settled on the third step from the top.

Pulling four blasters on people really did wonders for expanding your personal bubble.

"haven't talked with you much in the last couple of weeks" Sans said softly. It felt like the kind of atmosphere that called for quiet. That and there was a good chance Papyrus was still up. Sans didn't want to have to explain who he was talking to at 2am. "i was beginning to think you didn't like me any more."

"Yeah, well, not as much togetherness and interactin' and shit as before where I am now," the other monster said. His next words were deliberately neutral. It was hard for Sans to read his face in the dim light. "See your brother a lot more."

He would. Papyrus never really went into Sans's room much unless it was to get him up, and that would have been during the day. The other monster had challenged him to figure out where in the house he was... anchored to? Was that the right way to think about it? Anyway, Sans was pretty sure he was now haunting the super dark spot at the end of the hall. There should have been a window there. There wasn't. Now is was just the vaguely creepy spot near the bathroom where Sans could feel another presence if he lingered too long.

"don't let him see you." A pause as Sans considered it. "can he see you?"

"Tibia perfectly honest, I've been keeping a low profile around him." A shrug. "I don't know."

"i'd have a bone to pick with you if you kept popping up around him."

"Would you stop ribbing me as well?" Sans always did appreciate a good pun.

"don't worry, i won't stop jawing with you if my brother sees you," Sans replied. "just keep to the straight and marrow when it comes to papyrus."

"Heh." Sans narrowed his eyes. He didn't understand what had caused that laugh. It was short and devoid of humor. Or like there was humor in the situation, but the monster didn't find it funny at all.

"you have a problem with my brother?"

"His name is Papyrus." It was not a question, but a statement.

Sans thought back to the incident in the mirror, looking at a reflection that was and was not his own. Did the other monster have a brother? Was his name also Papyrus? Did that mean their resemblance was more than just a creepy coincidence? He wanted to ask, but even thinking the question brought up a kind of soul clenching foreboding that stopped Sans every time.

"Not going to ask about it? Don't you want to know what my name is?" Sans narrowed his eyes. It almost sounded like the other monster knew he kept choking on the words. "You know my name. It's your name."

"sans." Somehow it was easier to say the answer than to ask the question in the first place.

Sans – the other Sans – didn't flinch, but his smile seemed to go brittle. "Fuck. That's goin' to get confusing quickly."

"so i'll give you a nickname."

"Why don't you give yourself a nickname?"

"because i was here first, dumbass." That at least startled a laugh out of the other him, some of the strange tension seeping out of his posture. Fuck. The other Sans was right. It was confusing. "i could call you red."

"Red huh? Not very original." But Red didn't seem displeased by the name.

"what can i say? i learned my naming technique from asgore."

If he hadn't been watching for it, Sans might have missed the way Red flinched at that name. Interesting. It was a question for another time, assuming that Sans could get it out without a feeling of dread holding the words in.

Before he could bullshit any more, a yawn took him by surprise. Sans squinched his eyes shut. It was no use. He'd never been able to force himself awake when sleep demanded his attention.

"Idiot." Red's expression didn't exactly soften, but it grew less harsh. "Go to sleep. I'll keep watch."

"can i trust you?"

"No." The answer was quick and decisive. It was tempered somewhat by the grin Red gave him, gold tooth gleaming in the low light. "But what else am I going to do if you dust? Read all your books until I can recite them in my sleep? Fuck that shit. It's sounds like work. I'll watch out for you."

Not the most comforting of statements. Strangely enough, Sans found himself drifting off almost immediately. Maybe he'd grown used to having someone in his room while he slept. It was dark, the blankets were warm, and someone was watching over him.

He had no nightmares.

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8. What you see is a figment of your imagination.

Papyrus didn't drink coffee. He said it tasted too much like regret. Sans hadn't been much of a fan of coffee until he started university. Academia was built on regrets and caffeine, so it was no surprise that he'd become addicted. Even after his advisor had taken himself out of existence by falling into the CORE and – ending Sans dreams of getting a PhD, making tenure, only teaching one class a week, and getting paid to think about physics for the rest of his life – forcing Sans to abruptly leave his program, he'd never kicked the habit.

Since Papyrus didn't drink coffee, he also didn't make it. Even when he got up before Sans. And Papyrus always got up before Sans. At this point, Sans no longer bothered to argue with him about it unless he just wanted the comfort of hearing Papyrus complain at him.

This morning there was coffee. Sweet, sweet coffee as black as the void until Sans dumped enough creamer in it to turn it milky. Sans stood beside the counter and ingested his caffeine.

"YOU COULD AT LEAST SIT AT THE TABLE AND PRETEND TO BE A CIVILIZED ADULT," Papyrus said.

He could. But would he? Sans took another long drink, refilled his mug, and wandered over to the table. Slowly. Mostly to hear Papyrus huff in frustration. Less than a minute later a plate of toast and eggs was placed on the table. The eggs were only slightly charred, and you could even see some brown on the toast.

That was suspicious.

"what's the occasion?"

"DOES IT NEED TO BE AN OCCASION FOR ME TO MAKE BREAKFAST?"

"considering you hate coffee and you're not eating as well, yep."

And Papyrus... hesitated. That was worrying enough that Sans put his mug down on the table. Papyrus pulled out a chair and sat down. He made sure to meet Sans's eyes. His brother didn't have the ability to read people like Sans did, but it certainly looked like he was going to try this morning. "ARE YOU PULLING A PRANK ON ME?"

"no more than usual."

"SANS." Behind Papyrus's usual exasperation there was a note of desperation.

"what do you think i'm doing?"

"I KEEP SEEING YOU WHEN I KNOW YOU ARE SLEEPING. IT HAS TO BE YOU BECAUSE IT LOOKS LIKE YOU. ONLY NOT YOU? SINCE YOU DON'T HAVE RED EYES? BUT WHEN I GO TO LOOK MORE CLOSELY NOT YOU IS NOT THERE. I WOULD THINK IT WAS A SHORTCUT EXCEPT THERE'S NO SOUND."

"oh."

"YOU KNOW WHAT'S GOING ON." Papyrus looked hopeful. "TELL ME."

Now it was Sans's turn to hesitate. It sounded crazy. It was crazy. But was a monster living under a bed any crazier than what had happened to them in the Underground?

"there's a monster under my bed."

"I DON'T EVEN LET ROOMBA 2 UNDER YOUR BED."

Roomba 2 was the replacement for their first roomba, Roomba. Papyrus had been delighted by the little robot and insisted they refer to it by its name. Only then Papyrus decided Roomba needed an upgrade. Sans had come home from running his (still illegal) hotdog stand to find that Roomba had busted through the wall. He'd gently suggested that if he wasn't allowed to do experiments in the house perhaps Papyrus shouldn't either. His brother had looked at the Roomba shaped hole in the wall, then back at Sans before declaring "THAT'S FAIR."

As far as Sans knew, Roomba was still trundling forward in the wilderness in search of a wild charging station. Good luck, little buddy.

"i didn't let a monster under my bed. he just showed up and started living there. i haven't been able to figure out where he came from." I haven't asked. There was no reason to bring up that weird limitation.

There was a long pause where Papyrus considered the new bit of information. Sans took a piece of toast and started nibbling one of the least dark corners.

"THAT'S UNSANITARY." Sans shrugged. Couldn't really argue with that. Papyrus drummed his fingers on the table, a nervous habit he had when thinking. "WHY DOES HE LOOK LIKE YOU?"

"his name is sans. like me. he might be me. or a me. a... different sans."

"WELL THAT PROMISES TO GET CONFUSING QUICKLY." There was another pause as Papyrus once again considered the situation. "IS THERE ANOTHER PAPYRUS?"

"don't know. i haven't met one." Sans considered this for a moment. "you haven't seen anything strange in your room, have you?"

"UNLIKE YOU, I DON'T SPEND EIGHT HOURS OF THE DAY IN MY ROOM DOING NOTHING." Papyrus frowned. "I HAVEN'T NOTICED ANYTHING STRANGE. BUT IF THERE IS ANOTHER SANS THERE SHOULD BE ANOTHER PAPYRUS. HOW WOULD YOU SURVIVE IF YOU DIDN'T HAVE ME?"

"i know there's another asgore." Better not to mention the flinch that had accompanied that name. "i know he can teleport. i know he likes mustard like i like ketchup. i know he has my sense of humor."

Papyrus made a noise of disgust. "THERE IS AN AWFUL LOT YOU DON'T KNOW ABOUT HIM."

"you know how i get about too many questions," Sans replied. Then he paused, considering how this whole conversation started. "most times."

"YES, YES. YOU ARE A BALL OF OBFUSCATIONS AND TERRIBLE JOKES. IF THE OTHER SANS IS THE SAME, IT MUST BE GENETIC. WHAT A SHAME."

"what can i say? i'm well bread."

A huff. "THAT JOKE NEEDS A TOAST-MORTEM."

Sans grinned. "it's last, but not yeast."

"IT IS A BIT KNEADY THOUGH." When Papyrus spoke again, his voice was much quieter. "Can I meet him?"

Uh-oh. "pap. i don't know." Papyrus opened his mouth as if to argue. "It took weeks for him to even speak to me. he's only around at night. he's kind of cagey."

"WILL YOU ASK THOUGH? IF HE WILL MEET ME?"

He never had been able to say no to his brother. "i'll ask."

Chapter Text


9. No one will be there when you turn around.

There was absolutely no reason for Sans to be nervous. It was just... this was the first time he'd waited for Red to appear. Or really asked Red for a favor. Things would be different if it was something for him. Sans was used to disappointment. But this was for Papyrus, and Sans always hated disappointing Papyrus no matter how many times he managed to do so.

A sudden heaviness in the air was the only warning Sans had that Red was there. He'd deliberately left the lights off. Red didn't show up every night as far as Sans could tell, but he had wanted to increase the odds his doppelganger would show up tonight.

"Were you waitin' for me?" Red's voice was a mixture of sarcasm and self-satisfaction. Red eyes appeared in the darkness. "Couldn't get 'nough of my company?"

"well, i'm sure not here for your personality." Sans got up from his seat on the carpet. He did not want to have this conversation while being looked down on.

"Fuck you, I have a great personality." Red took another step from the shadows. There was a light on downstairs. Between it and the nightlight from the bathroom, Sans could see the glint of Red's gold tooth and the shape of his skull. His posture was relaxed. Sans could ease into the conversation, but sometimes these things were better if he just addressed them straight on.

"my brother wants to meet you."

"No."

Sans paused, waiting for an explanation. There wasn't one forth coming. Red's expression was shut down, giving Sans nothing. The other skeleton had tensed, but now he was deliberately relaxed. Too relaxed. Look at how much Red didn't care about his conversation. He was calling bullshit.

"why not?"

"Don't owe you shit."

"not even an explanation?"

"Nope."

Well. Here was a puzzle and a mystery. Sans might not be as good as his brother at puzzles, but that didn't mean he couldn't solve them if he put his mind to it. If he wanted to. Did he want to? Hell, maybe not for his own sake. But for Papyrus's sake? He at least wanted an explanation to temper his brother's disappointment.

"i'm not asking you to come to dinner. i'm just asking you to meet papyrus." Using the name was deliberate. Sans clocked the subtle flinch and tightening around Red's eyes. He could keep pushing, but Sans had a better idea. He smiled, making sure the just toe the line between sympathy and pity. "i understand though."

"Do you?" There was a lot of danger in those two words. The shadows seemed to grow, spilling down the hallway like ink and muffling the light. Sans stood his ground.

"don't worry. soon you'll want to meet him. you'll practically be asking to make his acquaintance."

Just like that, the mood shifted. Red narrowed his eyes. "What are you planning?"

Sans just smiled. "i don't owe you shit."

***

Three days later, Red found a note that had been left on the floor at the end of the hallway.

HELLO "RED",

MY BROTHER HAS TOLD ME THAT YOU ARE LIVING AT THE END OF THE HALL. THAT SEEMS LIKE A VERY UNCOMFORTABLE PLACE TO LIVE, BUT SANS ASSURES ME YOU ARE FINE WHERE YOU ARE. IF YOU NEED A BLANKET THERE ARE SOME IN THE CLOSET. WE HAVE EXTRA PILLOWS ON THE TOP SHELF AS WELL.

I HAVE ASKED MY BROTHER TO INTRODUCE US. IT IS ONLY FAIR THAT SINCE WE ARE GOING TO BE ROOMMATES FOR THE FORESEEABLE FUTURE THAT WE MEET. HE HAS TOLD ME THAT YOU HAVE DECLINED. I UNDERSTAND. IT IS VERY HARD TO BE INTRODUCED TO SOMEONE AS GREAT AS ME. I WILL CONTINUE TO BE AVAILABLE WHEN YOU ARE READY.

SANS HAS TOLD ME THAT YOU DO NOT HAVE VEGETABLES WHERE YOU ARE FROM. THAT SEEMS LIKE A GREAT TRAGEDY. LUCKILY I, THE GREAT PAPYRUS, KNOW ALL ABOUT COOKING VEGETABLES. EVEN IF MY BROTHER WON'T EAT THEM UNLESS THEY ARE COVERED IN KETCHUP. I AM TO UNDERSTAND THAT YOU PREFER MUSTARD.

I HAVE LEFT YOU SOME VEGETABLES IN THE FORM OF MY FAMOUS SPAGHETTI FOR YOU TO TRY. I COULD NOT INCLUDE MUSTARD IN IT, BUT WILL TRY TO ADD SOME TO DISHES IN THE FUTURE.

PAPYRUS.

Chapter Text

10. But there might have been.

"Stop telling your brother made up bullshit 'bout me."

The words were growled right behind him, coming from the dark as Sans made his way out of the bathroom and towards his room for the night. Red wasn't loud though. Papyrus was downstairs in the office on the internet, and Red wouldn't want to alert him to his presence.

"i don't know what you mean," Sans replied. He schooled his face into the blandest smile he could manage before turning around. Red was right behind him, looming out of the darkness. He wasn't very effective at it. When you were only a couple inches above five foot tall, it was hard to loom.

"I know what a vegetable is, you prick."

"wow. someone must have started a bunch of rumors about you." Looking wide eyed and innocent was a stretch for Sans, but that didn't mean he didn't try. He put a hand over his soul. "the nerve of some people. i guess you should talk to papyrus and get that straightened out."

Red glared at Sans. Sans smiled back.

"Ain't gonna happen," Red said. He didn't look away though, and Sans had to wonder if this was some sort of dominance thing. First to look away lost? He certainly seemed intent on holding Sans's gaze. "Tell him to stop leaving food for me."

"tell him yourself."

"Asshole."

"takes one to know one," Sans said serenely. "come on. don't you want to keep the peas?"

"I..." Sans could see the exact moment Red caught the pun. Sans watched Red's eyes narrow. "That romaines to be seen. Depends on how big a jerk you're going to be."

"it's not like pap will be jalapeño business." There was that flinch again, subtle but there, at the mention of Papyrus's name. It was a piece of the puzzle Sans already had. He just wasn't sure he liked the picture that was being revealed. "don't squash his hopes."

"Olive this needs to stop." Red took a step closer. Sans refused to back away and refused to drop his gaze. Red eyes bored into his own.

"or what?"

"Or I'll..."

"IS THAT RED UP THERE?" Both Sans and Red jumped, giving the downstairs equally furtive looks. How had Red managed to get so close? Papyrus didn't appear. His voice was the only thing that intruded on them. "TELL HIM HELLO AND THAT I WILL MEET HIM WHEN HE IS READY."

"Ain't never gonna be ready." Red grumbled. He stepped back, shoving his hands into the pockets of his jacket, his shoulders hunched up until it was hard to see the collar around his neck. There was a fine sheen of nervous sweat on Red's skull.

"ALSO THANK HIM FOR LEAVING THE EMPTY PLATE OUTSIDE MY DOOR. HE ACTUALLY RETURNS HIS DISHES UNLIKE SOME MONSTERS WHO JUST LEAVE IT TO MOULDER IN THEIR ROOM UNTIL I AM FORCED TO RETRIEVE IT."

"empty plate, huh?" Sans grin was delighted. His brother always did give him the best presents.

"I'm not gonna waste food," Red snapped.

"uh-huh. was it spaghetti?"

"He made the noodles out of zucchini." That made Sans's grin go sharp. Red grumbled. "Tell him to cook them longer. Noodles ain't supposed to be crunchy."

"you could always tell him yourself."

"Why are you so focused on me meetin' your brother?"

It was on the tip of his tongue to deflect, to give some sort of bullshit answer. The words didn't come. What came instead was the truth. It was a surprise even to Sans. "because my brother wants something and i want him to have it if he can."

"Yeah." Red looked away, as if the wall in the hallway suddenly held the answers to the universe. "I get that."

"do you?"

Instead of answering, Red stepped back into the shadows at the end of the hall. His outline went indistinct until only his eyes were visible. Then those also faded away into the darkness.

Sans's smile felt more genuine. Red might play at being an asshole, but Sans could see through him. Mostly because he was him. Sort of. And anyone who praised and ate Papyrus's cooking couldn't be all that bad.

Chapter Text

11. If you decide to cook something, always cook for two.

Papyrus was out of the house after nightfall – Undyne was dragging him out somewhere and Sans hoped they had fun – when he shortcutted upstairs. He could have walked. His brother would have scolded him for not walking. But honestly, Sans did not want to navigate the stairs while holding two plates with food on them.

"hey." It still felt weird talking to a dark hallway. Every time Sans did, he felt like this time he'd realize Red was all in his head and he had finally gone crazy. Tonight was not that time though. There was a sudden, reassuring pressure against his soul that sent a shiver down his spine. Two red eyes blinked out from the darkness.

"What'cha want?" Red asked. His words were rough, like he'd just woken up.

"got food for you."

"More veggies from your brother?" Red emerged from the shadows like the world's most emo skeleton. "My bones are goin' to turn green from all the grass." Despite his words, Red still reached out for the plate Sans offered.

"it's not from papyrus. i... i cooked it."

That got his attention. Red looked up sharply from the plate. "You know how to cook?"

"tori taught me," Sans admitted. He sat down in the hallway, his back against the wall. "i got much better once we got to the surface. before that tori gave me instructions and i had to figure them out back at the house.

"She was was givin' you instructions through the door." Red looked like he regretted his words as soon as he said them. Another piece of the puzzle. Red had a Toriel as well and she too had locked herself in the Ruins.

"i heat to say it, while i have some skill-et following instructions, hands on was much more a-peeling."

"Heh." Sans was surprised when Red settled down near him in the hall. He wasn't touchy-feely at the best of times. Ever since the whole blaster incident, he usually left even more room between them. There was a brief burst of warmth to see him... not trusting, but not untrusting either. "I guess you were cooking at your own whisk."

"the first thing tori taught me how to make was pie. the first time i made it, it was so bad papyrus thought it was supposed to be a quiche."

That earned him another look, followed by Red eyeing the slice of pie on his plate. "Didja make this using the old lady's recipe?"

"no. i found it on the undernet."

Sans didn’t understand why Red suddenly relaxed. He could ask. It was on the tip of his tongue to ask. Instead, Sans swallowed the words back. The food and a chance to just be companionable was a peace offering. Not that he was going to stop trying to get Red and Papyrus to meet, but he was sorry it had made Red's life more difficult.

"It's good," Red said, his mouth full of potatoes. Which was both disgusting and flattering. "Better than when I tried to cook."

"now you're just trying to curry favor," Sans replied.

"I'm just grilled to see real food," Red replied.

That could have been a dig at his brother's cooking, but Sans refused to take it that way. He dug into his own plate with gusto. It wasn't a fancy meal. Roasting the chicken involved sticking it in the oven until it was cooked. The hardest thing about making the potatoes was not turning them into glue when mashing them. Including carrots was a nod towards his brother's desire to something healthy on the plate. It also helped that they didn't taste green.

The pie was the most difficult thing to make. Sans had taken a shortcut (heh, he always did when he could) and used store bought crust and canned pumpkin. He didn't even need to add spices. The pumpkin came pre-spiced out of the can.

They ate in silence in the darkness of the hallway. Normally Sans wasn't a fan of silence. Too much room to think. This silence seem companionable. Intimate. Sans wanted to break the sudden weird tension in the air. He also wanted to stretch it out, let the tension between him and Red stretch on forever.

Red finished his plate with a loud belch, breaking the tension. Sans finished his plate and then let out an even louder belch. It wasn't like Papyrus was here to yell at him for it. Red laughed while San grinned.

It was a good night.

Looking at the narrow space between then, Sans wondered if he could make it better. He carefully moved over until the space disappeared. Red stiffened. "this okay? i can move."

A long pause. "Yeah. It's fine." Red was a line of warmth against his side. As the seconds ticked by and nothing happened, Red relaxed beside him. Sans pushed more of his weight against Red. He smiled when Red pushed back.

"i'm not going to stop trying to get you to meet my brother," Sans said. Instead of arguing, Red just shrugged. "you might as well give in."

Red's smile was all shark teeth. "I'll think about it."

Chapter Text

12. Do not worry about any of the above if you have a dog.

Papyrus kept leaving Sans alone in the house. He got it. He really did. His brother wanted Red to feel more comfortable in their house, and it was pretty obvious Red did not feel comfortable around Papyrus. So he spent more time with Undyne and Sans wound up spending more time with Red.

Normally, that would be fine. But over the last week or so something had gone off with Red. He was acting strange. Reclusive. Twitchy. Short-tempered.

Which meant it wasn't too much of a surprise when Red grabbed him from the darkness and got all up in his face. Sans figured it was only a matter of time before it came to a head.

"Well, well, well. If isn't Sans lurking up in the hallway." Red's voice was friendly. His eyes burned in the darkness. "You think you're so safe."

"i'm in my house," Sans said. He tried for casual, but didn't know how successful he was. "what could happen?"

"I could happen. That ever occur to you?"

"i'm not afraid of you."

"Not now. You should be. Didja even bother checkin' me?" Red asked. There was a feral look in his eyes. He scoffed without ever letting Sans answer the question. "'Course you didn't. You think ain't nothing bad going to happen to you."

"you never checked me."

"Did too. First night I was here. You didn't even wake up." The last statement was almost sneered. Red's grip on the front of Sans's hoodie tightened. "You soft monsters are pathetic. It's all rainbows and kittens and shit for you. Don't have to worry 'bout people trying to remove your soul through your ribs here."

There was no way Red didn't see the flinch. Sans couldn't help it. The memories were lurking like darkness behind his eyes.

"Or maybe you do. How many times did the kid reset?"

"fuck you."

"Naw, not right now. I'm more in the mood for violence." Red's grin was vicious. "Don't know why you're even upset. Your bro is still alive."

The realization fell on Sans like a bucket of ice water. He remembered the feel of dust against his bones when he picked up his brother's scarf, the thin smile of the kid with dead eyes, the feeling of helplessness as he watched everyone die, the smell of bleach and lemon used to clean the Judgement hall. All the things Sans had tried to forget welling up like a poisoned spring.

Red gave Sans a shake. "Maybe I was wrong. Maybe things didn't always go right." When Red laughed, it sounded a little unhinged. "Go on. Check me. Won't even be mad."

Sans did. He wasn't sure it was a great idea, but he did it anyway. Sans magic washed over Red in a wave, before returning to him with the information he didn't want.

* SANS - HP 5/5 LV 9
* He is grieving.

"fuck." Sans felt something sharp in his soul. And how long had he been pushing Red to meet Papyrus? He'd never thought of why Red kept declining. "i'm sorry."

"Don't you fuckin' dare." Red slammed him up against the wall, hard enough that Sans's teeth rattled. Not hard enough to do any damage to his HP though. "You don't get to apologize and think that's goin' to make it better. My brother is dead and yours is still alive. Stop rubbing it in my face all. the. time."

Magic surged in the air, so powerful Sans could taste it in the back of his throat. He braced himself for the attack. His own magic surged bringing with it a familiar mixture of anticipation and dread. This was going to be bad.

All fifty furry pounds of Annoying Dog suddenly came flying out of the kitchen at full speed. He watched as Annoying Dog barreled up the stairs, claws scrabbling and squeaky bark at full volume. Sans almost wished he had a camera. The look of pure shock on Red's face was priceless.

Sans thought it was a lot less priceless when Annoying Dog started circling Red while barking. Red turned towards the dog with murder in his eyes and bones forming around him. This was it. He was going to have to explain to Papyrus that his dog was dead because the mutt was trying to protect him.

Then he noticed that Red was fading out in front of his eyes. Red noticed it too. His grip on Sans's jacket loosened and he took a step back. Annoying Dog put himself between Red and Sans. Sans took a step back so he wouldn't trip over him.

"what the fu..."

Before he finished the last word, Red faded away. Annoying Dog stopped barking, prancing in place and giving Sans the look that meant he was convinced he was a very good dog. He wasn't sure whether to reward Annoying Dog's behavior or not.

He probably should. Annoying Dog had come to his rescue. "don't tell paps i told you, but there's some deli meat in the bottom drawer of the fridge beneath the lettuce."

Annoying Dog's tail was a blur of motion behind him before he raced towards the kitchen. Sans heard the refrigerator door open, the sound of a plastic drawer sliding out, and a triumphant bark. Then growling. Sans was definitely going to have to clean up the kitchen before Papyrus got home.

He looked at the kitchen, then back at where Red had stood just a few seconds before. His bones felt jittery from too much adrenaline. Red had tried to kill him. Or at least hurt him. He had LV.

And despite everything, Sans still hoped Red was all right.

Chapter Text

13. Stay awake.

Sans expected the nightmares to come back immediately. Being reminded of the resets? Remembering that he'd watched his brother die again and again? That was a recipe for Sans's own horrors to rise up in the darkness.

Of course, trauma never works like expected. The first five days after Red's outburst were some of the quietest sleep Sans has had in awhile. It was only on the sixth day, when Sans's mind gave him the thought what if Red never comes back, that the trouble started. The idea that the last thing Red would remember about Sans was that he and Papyrus had brought up his brother's death made him feel a little sick.

And the nightmares returned.

It had been over a week now, and Sans hadn't had a single night of uninterrupted sleep. It was beginning to weigh on him. Papyrus was giving him the concerned look every morning. Even a brand new bed wasn't helping. Getting eight solid hours a night seemed like a distant memory.

Which was why Sans was awake to hear the sound from his closet just a little after midnight.

Had he actually heard a noise from the closet? Or was he imagining things? Sans was tired enough that it was hard to tell. Then he heard the noise again. Nope. That was real.

He still wasn't used to the height of the bed. It was slightly lower than his old bed, but definitely higher than a mattress on the floor. Sans's foot hit the floor sooner than he was expecting. It sent a painful, jarring sensation up his leg.

That didn't stop him from stumbling over to the closet. The door was closed. Sans put his hand on it. "red?"

Silence. It went on long enough for Sans to start to feel a little weird about talking to an empty room. He was reaching for the door handle, when there was a response.

"What d'ya want?" Red didn't sound angry. He sounded tired. Resigned. This was his life and there was nothing he could do about it. That was even worse.

"i want to apologize."

"Don't need your pity."

"it's not..." Sans managed to catch himself. Getting upset wasn't going to help. How did Red always manage to do this? No one else could get under his calm like Red. "i'm going to open the door."

"Whatever."

There wasn’t much light in the room: the pale glow of moonlight competing with the yellow glow of a streetlamp. Even less light reached the inside of the closet when Sans opened the door. Sans honestly didn't remember there being this much crap in the closet. Then again, he didn't often open the door except to throw more crap into it. Red's eye lights glowed in the darkness, watching him from the corner.

"so this is cozy."

A shrug. Sans could barely see it in the light. "I've slept in worse."

But you don't have to. Sans kept the words trapped behind his teeth. What he felt wasn't pity, but Sans was pretty sure Red would see it that way. "there enough room for one more?"

Another pause. This time, when Red spoke, there was a thread of emotion in his voice. "Why? You got a bed."

"yeah, but i'm not sleeping in it. i figured i'd try something else."

"Alcohol works."

That startles a laugh without humor in it out of Sans. He walks over to the bed and pulls off a blanket. "no it doesn't. just makes me depressed."

"Not if you drink enough of it." Maybe it takes another Sans to hear the dark humor in Red's voice. He hums an agreement.

"i try not to let it get that far." The blanket it soft against his bones. "the one time i did, grillby woke me up with a bucket of snow dumped on my head."

Red's laugh was soft, but genuine. "Mine kicked my chair out from under me. Didn't do it there after that. If I was goin' to get really drunk, I did it on the couch." Sans threw the blanket over him as soon as he was in range. Red flailed a little bit until he got his head out. "What the fuck?"

"you're too boney to make a good pillow otherwise."

"Fuck you" The protest was half-hearted at best.

"nope." It was a tight fit in the closet, but Sans managed. He leaned all his weight against Red's shoulder. "i live here now."

"Asshole."

"takes one to know one."

***

Sometime during the night, the darkness and the warmth of the closet lulled him to sleep. When Sans woke up the next morning, Red was gone. Then blanket had been draped back over him. He felt a warmth in his soul that lasted until he saw the dick Red had drawn on his forehead in the bathroom mirror.

It took him almost fifteen minutes of scrubbing to get it off.

***

Papyrus doesn't say anything when Sans asked him where the boxes were from when they'd moved. He helped Sans carry them upstairs to his room with only a minimum of scolding. When Sans started digging junk out of his closet, Papyrus silently helped him pack it into the boxes. Sans thought he'd figured out when he retrieved extra blankets and a pillow from the closet in the hall. But he didn't say anything.

They hauled the boxes up to the attic. Sans had so helpfully labeled them: stuff, more stuff, junk, crap, more crap, and stuff 2.0 to which Papyrus had added Electric Boogaloo. Once that was done, Sans added a flashlight and a stack of physics books to the closet next.

He stepped back to survey his work. Papyrus spoke.

"I'M GLAD RED'S BACK."

"me too."

Chapter Text

14. Your friends cannot help you. You must face this alone.

Sans wasn't much for kids – for many, many reasons – but he put up with them in order to see Toriel. The kids she taught at the school tended to be on the younger side which helped. He had more luck with the younger ones. They didn't always get his puns, but they loved his knock-knock jokes.

For the most part, Sans got around the issue by seeing Toriel after school or during her free period when she was still doing paperwork, grading, working on lesson planning, or doing whatever it was that teachers did. In this case, it seemed to be trying to balance a pencil on her nose.

"knock knock"

Toriel jumped a bit, sending the pencil clattering to the floor. "Sans, you know you are not supposed to be in here." Despite her words, she smiled. "Who's there?"

He grinned. The policy was no unauthorized people on school grounds during the day and security all around the school enforce that policy. It wasn't very effective when monsters could teleport. "broken pencil."

"Broken pencil who?"

"never mind. it's pointless."

Toriel snorted as she picked up the pencil off the floor. "Did you come to see me just to share jokes with me?"

Both of them were always on the hunt for new material. Sans tended to search for jokes more often, but Toriel had an entire class of first graders who loved to share jokes with her. "have something a little more important to discuss." Despite being the one to bring up the topic, Sans hesitated. "have you heard any monsters complaining about things under their bed?"

From the doorway, there was a gasp. Sans looked over at the doorway to a human staring at him wide eyes. They were wearing a dark pink shirt with a glitter unicorn and floral patterned tights. The kid was at least a foot and a half shorter than he was. It was nice not to be the shortest person in the room.

"hey kid. i don't think we've met," Sans said, keeping his voice even and gentle. "i'm sans. sans the skeleton."

"Do monsters have monsters under their bed?"

It was a good thing that Sans had practice keeping his grin in place no matter what, because the little kid's question took all his words away. He looked at Toriel to see her reaction. Toriel just sighed.

"We talked about this Kaitlyn-child. Monsters don't live under beds. Fairies don't live in the woods. And humans don't have magic."

Now that was a familiar argument. Magic was everywhere in the Underground. Humans and some monsters, like Toriel, insisted that there was no magic above ground. Or at least, there hadn't been until monsters came above ground. The leading theory was that magic had been sealed along with the monsters, and only now was it beginning to leak out into the world above.

As far as Sans was concerned, that was bullshit. There had been magic above ground, just not as much as before monsters. It was there though. Sans could still see traces of it in movies and echoes of it in the stories humans told.

Obviously those stories involved monsters under beds. Interesting. Maybe it was just the memories of old times, but Sans didn't think that monsters had ever lived under beds.

Until now.

"let the kid talk," Sans said. "kaitlyn was it? what can you tell me about the monsters under the beds?"

"My parents say they aren't real," Kaitlyn said, ducking her head shyly.

"i believe you." Especially considering Red was now living in his closet.

"The monsters live in the dark. They can grab your ankles so you have to be really careful when you... when you get out of bed. And... and they have glowing eyes. And they're really scary. You can tell when they are there because you can. They can't get you if it's light so I have a nightlight." All the words came out in a rush, piling one on top of the other. Then her voice got softer and quieter, as if Kaitlyn just remembered she didn't know Sans. "Sometimes they live in the closet. Closet monsters."

"have you ever seen a under-the-bed monster?" Sans asked. Kaitlyn shook her head.

"Kaitlyn, does Mrs. Jacobs know you inside?"

"I have to go to the bathroom," Kaitlyn replied.

"Then you should go and go back to recess." Toriel's voice was kind, but firm. Kaitlyn gave a shy wave to Sans before she disappeared.

"You really shouldn't..."

"there's a monster living in my closet," Sans said, cutting off Toriel's words. "started off living under my bed like the kid said. he's upgraded."

"Sans..."

"no joke," Sans replied. "well, sometimes he's the joke. he also tells jokes. he's a sans. a more dangerous, darker version of me." Toriel went very, very still. That caught Sans's attention.

"I thought I was just hearing things," Toriel said. "At night. I would hear a voice that sounded like me telling jokes."

"what kind of jokes?" Sans asked. Amazingly, Toriel blushed.

"Jokes that I cannot repeat where little ears might hear them." Toriel shuffled the papers in front of her. "Why are they appearing now? What caused this?"

"i don't know. it could be excess magic manifesting itself using the humans belief system," Sans said. "or is could just be the universe fuc- um, messing with us." Toriel gave Sans a sharp look. "sorry, forgot there were kids around." And he'd been spending too much time around Red.

"But they are still monsters." It wasn't a question so much as a statement.

"yep."

"I know I am no longer your ruler, but someone should help them. If they need help. If they want it." Her eyes were kind, but knowing.

Toriel always did have too much faith in him. "i'll see what i can do."

Chapter Text

15. Never turn on the lights.

The first thing Sans did was research. It wasn't as easy as he was hoping. The internet was millions of times bigger than the Undernet, and filled with about a million times more weird stuff. That was saying something considering the Undernet had multiple moldsmol porn sites.

After wading through the horror movie pages, the band album pages, and oddly enough the porn sites, Sans was able to do actual research on monsters under the bed. It wasn't very enlightening. Humans thought monsters under the bed were nothing but kids imagination.

Yeah, he had an emo bastard currently living in his closet that said otherwise.

Sans was able to piece together one commonality. Monsters under the bed could only come out in the dark and disappeared during the day. Light kept them at bay. There wasn't much more than that beyond advice on how parents could calm their kids with fake "monster repellent" or white noise machines. It seemed that kids believing monsters lived in their rooms was so universal, no one bothered to describe them.

It was quite possibly the shoddiest research methodology Sans had ever had to deal with. And he'd had an advisor who tended to forget no one could read his font and write half his notes in wingdings.

"You're up late." The voice carried from his closet to his desk. Sans had his desk lamp on, but the rest of his room was pitch black.

"trying to figure a few things out," Sans replied. His eye sockets ached. That's what he got for putting in actual effort.

"Need help?"

"mostly i need to sleep," Sans replied.

"Can't help you there. I'd invite you back to my place, but I have too many skeletons in the closet as is," Red replied. Sans didn't doubt it. No matter how much he and Papyrus moved out, Sans's closet was still small.

Which gave Sans an idea. He needed to sleep. Red needed to sleep. There was a perfectly good bed. No one else seemed to be able to articulate the rules of how monsters under the bed interacted with the world. Maybe it was time to experiment.

Or maybe Sans just wanted to share a bed with Red. That was something to think about. Later. When he wasn’t so tired.

"hey red, what do you call a skeleton in the closet?" Sans walked over to the closet as he spoke. He could hear Red moving around as he got closer. The closet door was open and Sans could see red eyes watching him from near the closet floor.

"Don't know. What?"

"human hide and seek winner." The joke was a bit more morbid than Sans's usual fair. Which meant that Red loved it. Sans used his laughter to locate Red in the darkness. His fingers closed around Red's ulna and radius in the dark. The bones were thick and a bit rough.

"What'cha doin'?" Red didn't sound upset. More curious than anything. It didn't fool him. He could feel the sudden weight in the air, a tension that hadn't been there before.

"an experiment." Sans gently pulled Red up. There a brief resistance. Then Red decided to go along. He got up. There was another hesitation at the closet door. Magic ran across Sans's bones before it settle again. Red stiffened.

"How did you get me out of the closet?" There was a bit more strain to Red's voice.

"an experiment," Sans repeated. He pulled Red towards the bed. "one that involves you sleeping in an actual bed."

"Well, I love my bed, but I'd rather be in yours." Sans looked back to see Red leering. He rolled his eyes.

"just to sleep, asshole. even if somnophilia is your thing, keep it in your pants" This time Red's smile was a little more genuine.

"Or what? You'll kick me out of bed? Just means we can fuck on the floor." Despite his words, Red didn't try anything as they got into Sans bed. Which was a lot more difficult when Sans was trying to keep a hold of his wrist. Red didn’t bother to take off his jacket. He just kicked off his shoes and slid under the sheets. "Now what?"

"sleep." Sans closed his eyes as if to demonstrate. Red huffed a laugh, then shook his arm until Sans loosened his grip. He slid his hand down until fingers intertwined with Sans's. Holding hands. It was just practical. Never mind that it was also the most romantic gesture Sans had ever experienced.

That thought still lingered in his mind when Sans drifted off.

***

Sans woke to his own face.

No, not his own face. He didn't have a gold tooth or a cracked socket. Red's face. They had fallen asleep in his bed. Now it was morning and his hand was still in Red's.

Light filtered through the curtains. It was morning and Red was still there. Chalk one up to the scientific method. Sans watched Red sleep, noting that the circles under his eyes looked less dark. Sans had the urge to lean forward and kiss him. The impulse sat heavy on him, but he resisted it. Red looked different when he was asleep. Not younger. Less tense though. Sans found he didn't want this to pass, wanted to hit pause and hold on to this.

Time marched on though. More light came in through the windows. Red grumbled, turning his head into the pillow. "Five more minutes, Boss..."

Regretfully, Sans let go of Red's hand. Red slowly faded, his form growing more indistinct until the sheets crumpled back to the bed. There was only a faint, lingering warmth to indicate he'd even been them.

An experiment.

And Sans wasn't sure what the result told him other than he was getting in deep.

Chapter Text

16. Logic and reason will not help you in the dark.

Sans hadn't been down in the basement in a long time. Months really. He paused on the stairs, hand over the light switch, and facing the darkness, as he thought about it. The last time he'd been down here was before Red had showed up. Obviously, Red had proved to be a much more interesting subject than trying to get the machine fixed.

The basement flooded with light when Sans hit the switch. Despite this, it still looked dim. It always looked dim no matter how bright a bulb Sans put in the fixture. The light never seemed to quite reach the corners.

There wasn't much down here. The machine was down here, obviously, lurking in the farthest corner of the basement. There was also a table, a couple shelves, a chair, a toolbox, and a cot folded up against the wall for when Sans wanted to take a nap. He never wanted to take a nap near the machine. Just working on the machine triggered nightmares for days which in turn triggered his insomnia. They were wolves in sleep's clothing.

Sans wasn't really sure how the cot had gotten down here. He would think that Papyrus brought it down here, but Papyrus never come down here. They had the spoken rule about no experiments in the house and an unspoken rule that Sans could do whatever experiments he wanted to as long as they stayed confined to the basement.

Sans picked up the flashlight on the table as he went by. The flashlight helped counterbalance the weird dimness in the room. When it worked. Sans turned it on then smacked it a few times to get it working. The light it produced was weak. He pointed it at the machine.

Yep. That was the machine. Looked just like it always did. A few months ago, Sans would have described the feeling as terrifying. That wasn't the case. The response he had when Red did something creepy was terrifying. It got his magic moving, filled his bones with adrenaline, and forced him to react. The machine was something else entirely. It was quiet menace and existential dread. The kind of thing that made him want to curl into a corner and just give up.

The machine had always been more Gaster's project than his, even though the theory of it was based on his thesis. Gaster's expertise was integrating magic and science. Sans was content to know just enough about magic to understand physics.

Sans had started working on the machine to try to bring Gaster back after the whole CORE incident. He was not throwing away six years of hard work just because his advisor was an idiot who science himself out of existence. Then he'd worked on it as a form of self-punishment. This was where science got him. Nightmares and reboots and a feeling of helplessness when it all went wrong. Did he really want to do that?

The answer was yes. Kind of. Sans still hoped to get the machine working one day just to prove that his theories were correct. Maybe he'd manage to bring Gaster back. Or at least a Gaster from a world.

Sans froze half way across the room. The flashlight in his hand fell to the floor and flickered off. He ignored it. A Gaster. Like a slightly twisted version of himself that just happened to appear after he last messed with the machine.

There was a theory there, a breakthrough that Sans could see the edges of but couldn't yet articulate. But more important than the why was the how. How had the machine started working? When had it started working? And why was it not working now?

With just a few steps, Sans was across the room and examining the machine. It was plugged in, but not on. It never came completely on no matter how many times Sans flipped the switch. Now it sat like a dead thing. No lights. No sound. Nothing.

What had he been working on? Sans walked back to pick up the flashlight, hitting it several times to make it turn back on. The beam picked up the back panel, which was missing two screws. He had been working on the wiring. There was a screwdriver sitting on the floor from he hadn't bothered to put in the last two screws.

Seconds and a few curse words later, and Sans had the panel off. The inside was covered in black soot. It didn't take him long to find the culprit. A fuse had blown.

Would a blown fuse be enough to cause two worlds to collide? Was that what really happened? Sans didn't think it was. But what if the magical fields were still in flux when it happened? He was so close to understanding but the details were frustratingly vague.

Not for the first time, Sans wished Gaster was still around. He knew enough physics that Sans could bounce ideas off of him, but not so much that he was set in his thinking. Sans could talk to Alphys, but Alphys could only listen. She couldn't contribute.

But... he could bring one edgy bastard who was him down here to look at it and get his opinions. Sans had caught Red reading his copy of "Introduction to Superstrings and M-Theory." So he had to at least know the basics of physics.

He'd have to hold Red's hand the entire time. Sans felt magic rise to his cheeks as he turned the flashlight off. This was ridiculous. He was ridiculous. There was no reason to blush. All he was doing was hold hands. He'd done a lot more and a lot worse in college.

Still, it would be a good excuse to get some more physical contact in with Red.

Yeah, he was definitely going to bring Red down here.