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Guardian of Bones

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“here, lift this up and bring it over”

(Y/N) did as Horror asked, gripping the heavy, submarine-like, steel door and lifting it up and over her head. Horror had long since stopped gawking at the unexpected hardiness but he shouldn’t have been surprised. He’d watched you heal a wound that humans die from. He made the mistake of recalling that moment and shivered. She was terrifying and unorthodox. 

And yet, as he watched you humming away while you carried the door over to the broken machine, you seemed so casual and normal that he could have been fooled. He still had his doubts about you but he couldn't exactly get rid of you after seeing you with his brother. He hadn’t seen him that happy in a long time and it warmed his heart… so you were staying for now.

You were quick to offer to help him in fixing up the machine, he went to decline at first but thought it over before he answered. He was starting to repeat the same thing over and over. The sooner, the better. And if he had another pair of hands then it’ll be done quicker. His brother was also very agreeing that she should help, as long as she came to hang out with him afterwards. He couldn’t exactly say no anymore.

Reluctantly, he accepted the help and she gave a bright smile. He had to look away. Brightness had no place here. She had no place here. She had a nice, better universe to go to with sunshine and rainbows. The sooner she goes back to it, the better. He didn’t want her anywhere near him.

The more he watched her though, the more curious he became. He started to ask questions about her. And she trustingly and willing gave answers, even to go as far to tell him about her past. He almost didn’t believe her so he went silent again. A guardian? Suppose that would explain why she latched onto any chances to help.

“Here! Maybe this will help” A piece of paper was suddenly in front of his face, he had been zoning out while he fixed the door onto the machine. He almost snorted, finding it funny how she was doing it again. Doing things to help. What a strange girl, even after he attacked her with every intention of using her body for food, she was helping.

(Y/N) waved the paper a little. With an annoyed scowl, he took the paper out of his face and looked at it.

A colourful picture of a completed machine stared back at him. There was even a little smiley face in the corner and different colour arrows to label each part. He ignored all that and just focused on how it looks, studying each part of it.

This could work...


Reader POV


He didn’t seem to appreciate your colourful drawing but he did seem interested on the design of Sans’ machine. He really was a lot like Sans when he wasn’t holding his axe, he’d left it upstairs. You weren’t sure why, maybe he forgot it but a part of you was hoping he wanted to get along.

“is this the one that your Sans made?”

“Yeah! I mean, it’s made out of steels like yours and not rainbows…” You gave a light chuckle to yourself , he rolled his eyes “... but that is pretty much how it looked. I’m not sure about this but I heard him say it was powered by something called… Thorium? I’m no science whiz but I think that was what he said”

“thorium? if i’m lucky, there is some in the old lab. i’ll have to turn it into uranium first... i’ll leave that for last”

“Okay then! Anything else I can do? Anything else to lift?” You searched for something to do, wanting to be useful but it seemed you had just done the last of the heavy duty tasks. You smiled widely at him when he looked at you, his eyes got wide too, especially when you placed a hand on his shoulder “Just say the word and I’ll get it done!”

“i don’t need anymore help, go find someone else to bother” He snapped at you, jerking his shoulder away, not turning to look at you again although you could see the red glow from his eye had gotten brighter. His hand was clenching and unclenching. Ah, you’d pushed a bit too much. You chewed on the inside of your cheek and took a slow step back.

“Okay… I’ll just… go for a walk or something then”

You kept stepping back, watching him but he stayed still the entire time, keeping his attention on the machine. You stepped out the door, shutting it behind you and sucked in the cold air.

He wasn’t Sans, you really had to remember that, well he was but a much different Sans. He’s been through a lot and you needed to remember he needs his space. Guess you were just lonely, you missed all the skele-cuddles and love from your bunch of bonehead…

Well at least now, while Horror was occupied helping you, you could make a start on your plans to help too. Here goes nothing…

You began to head for Hotland, whistling quietly as you walked through Snowdin. The cheerful tune you went with seemed out of place for the location but you kept it going, it made you feel a little better. It gave you a dose of hope and courage. There weren’t many monsters around but the few that did see or hear you did nothing but either stare or run away, they seemed either scared of something that seemed stronger or they were still sizing you up. You felt the tune going still. Things would get better, you were going to make sure of that, they didn’t deserve this. It’ll be okay just as soon as you get them out of this dreadful place and into a entire world full of hope, possibilities and not to mention food and resources.

Each one that you saw now, with these thoughts, instead of seeing them as suffering monsters; you saw them as someone else you could save. You could see a light inside them, a glimmer of a happy future for each of them and you were determined to make them reality.

You glanced down a path, wondering where it would lead when you saw a cloaked figure standing on a boat. The boat looked worn and old but it was floating on the calm waters. They were doing nothing, just staring straight ahead, and even though you were sure they knew you were there; they weren’t running or looking at you like you were their first victim.

You carefully approached, clearing your throat first.

“Hi there. I’m sorry to bother you, I don’t suppose you could-

“Tra la la, care for a ride?” He started the sentence with a dull tune, he sounded fed up, as if he’s said it so many times it’s become boring.

“Ah, yes please. That would be great. Do I need to pay though or…?” You asked as you carefully climbed on. The wood gave a creak and very carefully knelt behind him.

“My service does not require pay. Where will we go today?”

You cracked a small smile at the, probably, unintended rhyming words and quietly voiced Hotland. Just as the boat began to glide through the water, someone climbed on beside you and sat down. You looked up to find Pasta, who was looking down with a slight saddened expression.

“I SAW YOU LEAVE AND DECIDED TO FOLLOW YOU, I THOUGHT PERHAPS YOU WERE SEARCHING FOR ME BUT… WHY ARE YOU GOING ALL THE WAY TO HOTLAND?” He tilted his head, you chewed on the inside of your cheek some more. Maybe you could tell him what you were planning, he could even help you!

And so, you told him that you were going to talk to Undyne. He jolted, rocking the boat with his movements and began to wildly disagree with the idea as he asked the cloaked figure to turn back.

“Tra la la, the angel is here” was the only response he gave, Pasta became more distressed and you gently placed a hand on his arm.

“We must not see Undyne, you do not understand” His voice was quieter as he trembled slightly, you kept your hand on his arm and listened “She is… no longer my friend because... she does not believe in kindness, she will hurt you and I do not want to lose you”

“You’re not going to lose me, I promise. But I have to do this. I have to talk to her, even if it leads to a fight, I can handle it and I will survive” You gently wrapped your arms around his tall frame, holding him for a moment before releasing him “I can’t save everyone without seeing her first”

He was tearing up again, you knelt up and caught a few tears before they could fall, wiping them with a thumb. “Please don’t cry, it’s going to be okay”

With a few shaky breaths, he did calm down before giving you a tight hug just as the boat reached Hotland. You thanked the figure, who gave a slight nod and began your walk towards the castle, now lead by Pasta who was back to himself again.


You gave a small chuckle and stepped into an elevator with him, watching him struggling for a moment to press the bottom with his large, gloved finger. It was much cooler in here than it was out there, Hotland was appropriately named. You began to hum again, barely noticing Pasta listening with a small smile as he enjoyed the sound.

He took you through many halls, some had guards but Pasta pretended he was taking you to Undyne for execution. They seemed to believe it, luckily, and you progressed with no fuss. Until finally, you were outside the throne room. You gave Pasta one more, quick hug and reassurance before pushing open the doors.

You were met with blood, lots of blood, staining the bed of golden flowers that littered the ground and mangled bodies was scattered everywhere, with no heads.

Next to a large, golden throne, you found the heads. Each one with lined up beside the throne and on a pike. You weren’t sure if they were trophies or to ward off challengers. And of course, on the throne, was a woman who looked an awful lot like the Undyne you knew.

She wore red armour with the rune you’d seen on Toriel's clothing, the chest plate only covered her top half and showed her stomach where you could make out gills. Her hair was up like always but it was messily done, around her ponytail was a crown and a white bandage covered her eye.

“Well, well. Papyrus, you’ve actually done something useful for once” She sneered as she relaxed in his throne, her legs over one side. “Get out now, I don’t want you here to ruin my fun”

Pasta hesitates beside you while you keep your eyes directed on Undyne, you wanted to look at him but you keep her fixed with a steely expression. She was unpredictable and for what Pasta had warned you, she could attack if given the chance. She sat up slightly and bares her incredibly sharp teeth, snapping at Pasta who flinched.


You nudge him gently, whispering for him to wait outside. He hesitates again, looking at you then Undyne then nods, walking slowly and dejectedly out the door. It crushes your heart.

“I haven’t come here to fight” You admit when he’s gone. You take a moment to look more at the flowers “I’ve come here to offer you freedom, but only under some conditions. They shouldn’t be that hard to meet as long as you’re feeling…”

A spear goes flying towards you, catching it out the corner of your eye, you manage to get out of the way before it can touch you. You finish “... agreeable"

“We only need one more soul, you think I'm going to give up now? I am going to enjoy this!”

She tosses another one, you dodge again. She keeps them coming and with each one, your diving brings you closer to her until you are before her. She has another spear ready and tries to slice you with it, pushing herself off her throne but you grab the middle and use it to hold her down in a sitting position while she struggles.

“So here’s the deal. Two conditions. Firstly, you stop killing. There isn’t any need for it anymore, I’m going to break the barrier with my magic. I am well versed in barrier magic and this one will take seconds” You have to push a little harder, she’s strong and fighting back the entire time. You can only imagine how much LOVE and EXP she has gained through killing so many humans... and monsters you don’t doubt.  “Secondly, you pass the crown over to Toriel. She is the rightful queen and the one that everyone needs”

“I’ll tell you what… I’ll make my own deal…” She growls out between the struggling “We fight. With no dodging bullshit. And if you win, then I’ll agree to those terms. If you lose then you break the barrier for free and monsters can finally get revenge!”

“Fine!” You yell with one final push, that sends her so far back into the throne that it flips backwards.

She rises from behind it, spear in hand, seemingly excited. You watched her jump on top of it and yell. “Alright punk! LET’S FIGHT!”

She dashed at you with a warrior cry, you barely had enough time to summon your wrench and when you do, it doesn’t come like it should.

Panic ensues when you remember that it’s all the way back in Undertale, there’s no way it’s going to get to you from another universe so you had no weapon to fight back. You can open portals with your wrench but only when you control it, it can't just come through itself.

Keeping your word not to dodge, you had no chance but to take the blow. It was too late to come up with an alternative idea. Her spear slashed through the skin on your stomach and you gave a hiss of pain, stumbling back a moment. Your shirt quickly became covered in blood and this time, you threw your arms up in a cross to guard your body as she didn’t waste anytime throwing in another.

Using your now sliced arms, you pushed her back. She stumbled a step then you threw yourself forward. You had no choice but to fight with your fists. She cackled, catching both fists strongly and tightly and leaning into your face.

“You can’t even summon a weapon? How pathetic. Just like Papyrus. And you two seem like buddies too. I sure hope you haven't been teaching him mercy. He's too nice already. He doesn't listen, even when I have to beat it into him"

You pushed your fists harder into her hands, angry at she hurt him but deciding not to rise to that and instead, yelling “Why bother with revenge? The humans that trapped monsters underground are long gone and dead! The humans of today are nothing like that! If you give them a chance, they’ll give monsters a chance too! BUT NOT IF YOU ACT LIKE THIS! THIS IS WRONG!”

She pushed you back furiously, seeming to have lost the thrill for this battle now that you were questioning her choices as queen and calling them wrong. You thought you saw her glance at her head collection but she was quickly back to tossing spears your way. You didn’t dodge, you managed to catch the first one and hurl it back. It narrowly missed her shoulder but paused her long enough for you to launch at her before she could get any more.

“NO! This isn’t just about those humans that trapped us! You can’t tell me that there aren’t bad humans out there, ones that will want us to stay down here and rot! THAT’S WHAT FRISK WANTED! They would have helped otherwise, they would have done something! BUT THEY JUST LEFT US HERE! HUMANS AREN’T WORTH SPARING!”

You shoved her down as she prepared another spear, sitting on her stomach and holding the spear firmly above her neck, keeping her on the ground while you yelled at her, frustrated.

“YOU ARE WRONG! Sure, there are bad humans, but there’s bad in every species! I mean, look at monsters! You are meant to be made out of love and here you are, KILLING AND LOOKING FOR REVENGE! So if that’s the way you think, then why should monsters leave the underground if they are just as bad as the humans you despise?! THERE'S NO DIFFERENCE BETWEEN YOU THAN APPEARANCE”

She gave a frustrated scream, finally managing to push you off before throwing multiple spears at you all at once. You had no choice but to ignore the rules and dodge, but you couldn’t dodge them all.

They scraped your arms, legs and everywhere they could reach while you struggled to stay upright.

Dodging became harder and you got sloppy enough for one to go through your shoulder, as if revenge for earlier, and another cut your cheek. You could feel the blood trickle down to your jaw.

With a louder scream, her eye glowing dark yellow, she bolted towards you with a spear pointed at your head. You braced yourself.

And there was no pain.

Pasta was stood in front of you, shakily holding the spear. His entire body was quaking so hard that you could hear his bones rattling. Undyne stared at him with a glare, he looked back with a worried and sweaty expression.


Undyne growled, you held a hand over your shoulder, unsure whether to step in between them or to allow Pasta to say what he needs to.

“Papyrus… Move... Now”


She was quiet. You were terrified she would hurt him but you could barely move and something was keeping you in place. You suddenly realized it was Pasta’s magic, he was weighing you down with blue magic.

“PLEASE… UNDYNE. PLEASE STOP…" He moved a hand across the spear and rested it on top of hers "...I STILL BELIEVE IN YOU, UNDYNE. YOU CAN DO A LITTLE BETTER… I PROMISE…!”

Slowly, tears began to fall from her eye. You could see the bandage becoming damp. She let go of the spear and it dematerialized before it hit the ground. Pasta had his arms around her immediately, without fear, and for a moment, you were still scared. Then she slumped into him and cried harder, muttering apologies between heavy breathes. You were filled with relief.

You sat down on the flowers and watched, exhausted but smiling despite the pain as you pull the spear out your shoulder. You tried not to make any noises and interrupt them. Pasta was crying too and they both end up on the flowers in front of you, kneeling and hugging.

After a considerable amount of time, they calmed down and Undyne agreed to give up the throne to Toriel if she will agree take over. You explain you were going to go find her next and talk to her but Undyne was the “biggest fish to fry”

You almost thought she was going to try and kill you again after that unintentional pun slipped out, but after Pasta gave a wail of agony, she actually smiled even if it was a sad one. You could see she was remembering better times.

You promised to come back after talking to Toriel and you asked her to start preparing monsters to leave the underground, and to make sure they understand the change in plans. No humans harm.

She agreed and Pasta stayed with her to help, you were worried to leave him there for a moment but he was the one reassuring you this time. You left quietly, shutting the door behind you and slumping against it for a moment, your body stinging and dripping blood in various places.


“... Ouch