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Like Sugar in Dark Chocolate

Chapter Text

Sans cursed at his life choices for the upteenth time as he led not-Papyrus through Snowdin Forest, trying to find a good training ground. He remembered a clearing up in the far north, away from the town and hopefully the watchful eyes of the Royal Guards. His fists clenched tightly in his jacket pocket, surveying the clearing. This looked like a good spot.

“WOWIE! THIS PLACE IS PERFECT FOR TRAINING!” not-Papyrus exclaimed, running into the clearing.

Sans shuffled over towards the tall skeleton, doubt surfacing quickly. He still wondered what in the stars had him agreeing to all this. Was he that pathetic and desperate that he allowed himself to get wooed over by a couple of letters?

He glared at the smiling skeleton in front of him. How could someone be that trusting? Even though it boggled his mind, he couldn’t help but feel himself, like a moth to light, becoming drawn to not-Papyrus’s bright disposition. He would never admit it to the tall skeleton, though, and try as hard as he could to deny his feelings.

Sans let out a huff before facing not-Papyrus, “so how’s this gonna work? you gonna allow me to attack ya?”

Not-Papyrus stroked his chin thoughtfully with his gloved hands. Sans noticed that the gloves were more rounded than the ones Boss typically wore.


The short skeleton narrowed his sockets at not-Papyrus from the suggestion, suddenly wishing he’d never agreed to this and was back sleeping in his room.

“how? what d’ya want me to do?”


Sans concentrated and grasped at his magic. He felt a burst of power, way more than necessary, and summoned a red-colored bone hovering behind his left shoulder. Without warning, Sans felt a huge surge, and before he could control it, the bone went flying towards not-Papyrus. The tall skeleton summoned a bone of his own and intercepted Sans’s attack.

The short skeleton’s face flushed light pink in embarrassment. He couldn’t even control a simple bone!

Not-Papyrus stared at the destroyed red construct thoughtfully before beaming at Sans. His flushed cheekbones deepened in response.


Sans bristled. “of course!”

Not-Papyrus charged towards Sans with a long bone staff in his hand. Sans focused and a row of white bones erupted from the ground in front of him as a barrier. Not-Papyrus swung his weapon and Sans blocked. Once again, he felt a gush of uncontrollable magic. He tried to suppressing it. Like putting a lid on top of a shaken can of soda, the power was too much and backfired, sending Sans crashing into a pile of snow.

“ARE YOU ALRIGHT?!” Not-Papyrus’s loud and concerned voice flooded his hearing.

A burst of anger and indignation flooded him as he got up. “’m fine. what kinda stupid monster are ya askin’ that type of questions?” he retorted. He’ll prove to the tall skeleton that he was not weak. “i’ll make sure ya regret underestimatin’ me.”

Crimson magic burst forth from him and jagged bones erupted from the ground. Sans’s magic sputtered out and a gaster blaster suddenly materialized in front of Papyrus, who appeared shocked. A red beam of light began to charge.


The beam of concentrated magic shot out of the blaster.

Sans stared at not-Papyrus, his sockets completely black, and ordered, “G e t o u t o f t h e w a y!”

Not-Papyrus ducked into the snow just as the attack shot over his head. The line of trees behind him disintegrated completely.

Sans shuddered painfully as he forced the blaster away. Sweat dotted his forehead. Not-Papyrus picked himself off the snow-covered ground and ran towards him, distress etched on his features.

“RED? DO YOU HAVE ANY IDEA WHY YOUR MAGIC IS SO… unstable?” not-Papyrus at least had the decency to say the last word quietly, though it felt like a slap in the face to Sans nevertheless.

“nope,” Sans growled shortly, hoping to drop the topic. Like hell he was gonna tell this skeleton his life story.


Irritation and indignant anger flooded him once again. Sans found not-Papyrus’s concern belittling.

“it’s not a condition! this is stupid and pointless! you don’t know anything! i’m leaving!”


“forget this!”

Before not-Papyrus could get another word in, Sans ran back into the forest as fast as he could to get away from not-Papyrus. The truth of the matter was, he knew why his magic was unstable— getting forced into summoning gaster blasters before he could even summon normal bone attacks, not to mention all the Determination that’s circulating within him. The worst part of all this was the gradual loss of his magic control; it didn’t happen overnight. He also partly blamed this as the cause of the broken relationship he had with Boss.

Sans sighed as he trudged through the snow. He could really use some mustard right now. Grillby’s sounded like a best bet. The canine unit shouldn’t be there at this time, given that they were on rounds. Though without Boss here, who knows what they’re up to. He could hopefully at least extract some information from the fire elemental.

The short skeleton took several deep breaths before he walked into the bar. The chatter of noise went completely silent as all eyes fell on him. Sans clenched his fists in nervousness within his jacket pocket before shuffling over to the bar counter, ignoring the looks as best as he could, and slumped onto his usual seat.

“order of the usual, gillbz.”

The fire monster’s purple flames flickered with acknowledgment. He disappeared into his backroom and came back with a burger and bottle of mustard. Sans nursed the yellow condiment as he picked up the whispers of conversation. Lots of them were rumors about Boss’s disappearance and talks of gang fights beginning to break out in town. Sans shook with fury at the snide comments made about him. The assholes weren’t even discrete about it, talking loud enough so he could hear. He was about to get up and leave but felt a warm hand on his left shoulder.

“Ignore them. Come to my backroom.”

Sans barely gave a nod before he was hoisted up from his seat and over the counter. Grillby’s flames changed to white with anger at the stares the patrons gave him. They knew not to get on Grillby’s bad side and went back to their conversations. Sans gave him a look of appreciation and followed him into the back room. As soon as the door closed, Grillby leaned down close to Sans’s non-existent ears.

“I’ve missed you, Sans.” His voice was low and sensual. Grillby’s flaming hand trailed up Sans’s chest suggestively, forcing a moan out of the short skeleton. “You’re stressed. I can provide you with some relief. Besides, your brother’s not here to get in our way.”

“grillbz,” Sans gasped, pulling away from the warm touches.

This wasn’t right. He wasn’t going to make this mistake again.

“stop. boss had nothing t’do with me breakin’ up with you.”

The fire monster froze. His flames crackled and turned a shade of cyan. That last comment made his fire sizzle with restrained anger.

“You lie! He had everything to do with what happened to us. What we had together.”

Sans narrowed his sockets furiously and snarled back, “you keep boss outta this!”

Grillby’s flames turned white. “Are you blind?! That spoiled brat was clearly jealous that you were spending more time with me instead of him. And then once he became Captain of the Royal Guard, he abandoned you like trash!”

“y’know what, fuck you grillbz! you don’t know anything! we’re not getting back together and that’s final! i’m leavin’!”

Sans took a hold of his volatile magic, preparing to shortcut back home.

“Don’t leave! You’ll regret this, Sans! I’ll make sure of it!” the bartender roared.

Sans ignored the flame monster’s threats and disappeared. He landed in his bedroom, taking deep breaths to calm his seething. Never before had he gotten this angry at Grillby. He couldn’t believe the selfish bastard had enough gall as to assume his brother had anything to do with their breakup. Their short time together had been just a fling and nothing more; the two of them even discussed and agreed to it.

The scarred skeleton threw himself into his worn mattress. He needed to nap all this away. This whole day had been shit except for getting those letters from not-Papyrus. Even then, thinking about not-Papyrus and their “training session” did nothing to curb his anger. Then he felt bad for abandoning not-Papyrus without even saying a word, especially since the tall skeleton was only trying to help him.

Red let out a sigh. He forced himself to sleep.

Sans found himself staring at a strange scene. Boss stood in front of an angry fish woman, Undyne, with a blue spear pointed at Boss.

“NGAAAAAHHHH! WHAT DID YOU DO TO PAPYRUS, YOU IMPOSTER?!” Undyne roared. She thrusted several spear attacks at Boss, who parried them with his bone staff.


Questions whirled in Sans’s head as he observed the scene. This Undyne looked different from the one he knew. Why was she attacking Boss?

Snow flew through the air as the two monsters thrusted their weapons at each other in close melee combat. Bone and spear pattern bullets flew out from Boss and Undyne, respectively. Boss blocked each of Undyne’s spear attacks without much trouble.

Sans watched as Undyne finally landed two damaging on his brother, causing his HP to drop. Boss suddenly froze in place, trapped in a barrier of green magic. Undyne stood before him, spear pointed directly at his chest.

“You’re not the Papyrus I know! A teenager comedian, that snowdrake, is dead because of you! To believe a monster would harm its own kind!” Undyne spat. “You’re just a coward who’s hiding behind that lazy, no good brother of the real Papyrus!”

Sans’s big brother instincts told him to move and help defend Boss. What was he doing just standing there and watching?

He heard a roar as huge spikes of bone to sprout from the ground.

Sans blinked awake, staring at his crack-filled ceiling. Was that some strange dream of the world that his brother was currently in, the one that not-Papyrus came from? Undyne was attacking his brother!

The short skeleton shot up and scrambled out of his room. He opened the door to Boss’s room, finding in unoccupied. Everything was neatly laid out in place. The four-poster bed stood in the far back corner, his miniature map of the Underground with the carved pieces of all the major monsters stood in the back wall opposite of the bed, and the desk and computer was placed on the left of the door entrance.

Finding nothing unusual, Sans went through his house to look for not-Papyrus before realizing that he’d never invited the tall skeleton back into his home. A loud curse escaped his mouth before he wrenched open the door and went outside. Night, or at least the pretense of night in the Underground, settled upon Snowdin.

Sans ran towards the Shop, hoping that he would find not-Papyrus there. He had to figure out if his brother was ok.

He slammed the door open. Three pairs of eyes stared at him in shock. He was too frantic to acknowledge Flowey as one of the pair.


“boss! he got attacked by undyne! i gotta get to him!”


“a dream, i saw him gettin’ attacked in my dream!”

The foreign Papyrus frowned at Sans’s outburst. He walked towards Sans and placed a comforting hand on his shoulder.


Sans distrusted the claim as he had clearly seen Boss getting attacked.

“i saw her attack boss!”

“Maybe you saw wrong?” Flowey interjected. “Dreams are rarely true. It could be that you’re simply worried about your brother.”

Sans summoned a bone and shot it in Flowey’s direction. The flower quickly ducked out of the attack, causing the construct to embed itself into the wall. The Shopkeeper let out a disgruntled scream at Sans.

“shut your mouth, you stupid flower. you expect me to believe she won’t kill boss? undyne always had a bone to pick with him.”

“YOU’RE WRONG RED!” the short monster was surprised to hear a tinge of anger in not-Papyrus’s voice. “UNDYNE WOULD NEVER KILL SOMEONE WITHOUT REASON! MONSTERS ARE KNOWN TO SHOW MERCY AND FORGIVENESS IN MY UNIVERSE!”

Sans scoffed at the claim.


Sans was still skeptical as he didn’t see his double do anything. He wasn’t even in the scene. Panic began to seep into him.

“If you’d agreed to work with us, we can figure out what’s going on with your brother. Why else did you think I suggested we work together! “ Flowey shouted at him.

Flowey was propped on not-Papyrus’s right shoulder and gazed intently at Sans, causing him to ready another attack.

“You will stop attacking this instant!” the bunny shopkeeper roared.

Sans’s magic sputtered out before he could even summon anything. With not-Papyrus, Flowey and the Shopkeeper all glaring at him, Sans suddenly felt like he was suffocating. Panic flooded his soul and his breaths came out as heaving gasps.

Didn’t they see how Boss was in danger? What’s gonna happen to him if he never sees his brother again?

Black spots appeared in his vision as he found it difficult to breath. He felt as if he were dying.


Was someone calling his name?


Was that his brother’s voice? It sounded like him.

Sans felt a pair of long, bony arms wrapped around him. A white chest plate heaved in and out against the side of his skull.

“Breath with me. You are safe, you’re brother will be safe. In and out like I am doing.”

Sans listened to the monster’s instructions and took in deep breaths following the rise and fall of his brother’s chest—wait no, this wasn’t his brother. It was the other Papyrus, the one that was kind and full of mercy. Boss was safe. His brother was safe.

His panic finally settled and his breathing went back to normal.

“I’m sorry, Red, we did not mean to frighten you,” not-Papyrus apologize. A hand soothingly stroked his back. “I, the Great Papyrus, promise that I will give my best effort to help you and your brother. Please trust me when I say that Undyne will not kill your brother. She is a great friend of mine, after all.”

“ok... i believe you,” Sans whispered. He would allow himself to trust this monster. This Papyrus had proven himself enough already.

Exhaustion washed over him. He collapsed limply in the arms embracing him. He was about ready for another nap.


For the next few days, Sans finally put more effort into his training. He had to admit that Papyrus was a good, maybe even great, instructor. Although his enthusiasm was still a bit much for the short skeleton, he always offered unconditional help.

“HAVE YOU EVER TRIED IMAGINING SOMETHING TO HELP CHANNEL YOUR MAGIC?” Papyrus questioned during day two of their training session. “IT MAY HELP YOUR CONTROL.”

Sans blinked out his eye lights and visualized a long tube with two lenses at the end. A device that allowed one to see far distances. A telescope. Using his imagined telescope, he pushed his magic through the tube and summoned a column of bones. He then dismissed them without issue. He even attempted to summon a blaster in the same manner. He did feel a huge burst of magic but then forced it through the tube of his imaginary telescope. With this method, he felt his control improve.

The two skeletons sparred in the early mornings, trading rounds of bone attacks. The more Sans trained, the more control he felt like he gained. There were, of course, still instances where his magic would become too unstable; however, they were fewer than it had been in years. Finally grasping some semblance of control over his magic had also made him happier than he had felt in a long time.

He also began to begrudgingly help Flowey, Papyrus, and Hariet in coming up with a plan to change the Underground. Both Flowey and Hariet had apologized earlier for setting him off into that panic attack, which he brushed off with a pun. Truthfully, he hadn’t even expected them to apologize at all so it’s no skin off his bones, heh. He’d thanked Papyrus for helping him come down from it, wondering how the tall skeleton know what to do.

On the third day after training, Sans went back to his house to find it completely trashed. All the windows were smashed and two words were repeatedly written all over his front walls.

Inferno. Hunters.

Papyrus, ever being the expressive and emotional monster, cried at the sight. The short skeleton appreciated the concern on his behalf but eventually convinced the tall skeleton that it was fine. He’d simply have to clean up and fix the mess before Boss came back. He was much more concerned about the note he found stuck on his front door.

I warned you that you will regret this!

Even without a name, Sans knew who wrote it. Papyrus insisted that Sans live with him in the Shop instead of his house, claiming it to be too dangerous. He agreed, finding that he immensely enjoyed spending time with Papyrus, even if it had to include Flowey.

“RED, I WANT TO ASK YOU,” Papyrus said later that evening. The tall skeleton wrung his gloved hands nervously together.

Oh boy, this was probably gonna be a loaded question.


“What did those two words mean?”

Sans still found it surprising that Papyrus could talk in a softer voice; he simply chose not to do it most of the time. His mind then processed the question and sighed. He definitely should’ve expected something like this.

“they’re names of two gangs me and boss were a part of when we were younger.”

“I see.” Papyrus kept silent but by the way he was fidgeting, Sans could tell he was going to get a follow up question. Sans decided to save him from the trouble of asking.

“since it’s almost bedtime, you wanna hear a bedtime story?”

The tall skeleton’s excited sockets practically glittered like stars. Sans chuckled lightly before he began his story.