Chainsmoker [ Gaster!Sans x Reader ]

11. Ghost I Never Knew

This was it.

Every moment, every word, every action it seemed, had led to this very moment.

The Core, once simply another landmark to be passed through, had become all-too important. It was here that you would commit the ultimate sacrifice, restart the timeline and free monsterkind, all at the convenient price of one human soul!

Slowly, the two of you walked into the abandoned MTT resort hotel, eyes trained only on the ceiling, the one part of the place that wasn't covered in dust and knife slashes. You felt G's bony fingers intertwine with your's.

I don't want to die, you thought and almost paused, attempting to restrain the burst of hysteric laughter that had been threatening to spill for quite some time now. Wasn't it just funny that you, of all people, were thinking that? How many times had you heard those words from a dying monster's mouth, shaking as you hovered over them, knife in hand?

How things change, oh how they change.

The Core was a series of winding tunnels, each covered in layers of dust from the monsters you had so carefully hunted down. "I'm going to set them all free," you declared to no one in particular. You looked up at G, tears in your eyes. "I'm going to free them all, right?"

G nodded, refusing to make eye contact with you. "That's right pixie stick," he murmured and squeezed your hand once for reassurance.

How much you wanted to stay, to stay with him. It didn't matter if you were to be forever condemned to a doomed world with no one but G, at least you would be there, with him.

You progressed through the Core, too fast, it seemed, a mockery at your sudden new value over life. You just wanted to live, was that so much to ask?

How the might have fallen.

There it was, in all of its glory, the Core. Located at the very center of the Earth, the invention that Gaster had labored on for years, centuries, maybe, to give monsterkind light in the darkness. G shared in your revelation, most likely recalling memories that he shared with Gaster, tireless nights and the ultimate satisfaction when the lights came on for the first time.

"That switch over there," G murmured, motioning to a big red lever properly titled with the word 'Power.' "It requires energy that can only be obtained through a human soul to operate successfully."

You trailed your fingers over the red metal, wondering what the other children who had sacrificed themselves had felt, knowing that once they pulled this switch and threw themselves into the lava below, it would all be over...

But didn't you owe that to monsterkind? Your penance to atone for all the crimes against them you had committed?

Your eyes wandered to G. But what about him? He was forever damned to stay alone in this empty world. Because once the seven human souls were collected in order to break the Barrier, no one else would come through here. He would be doomed to rot alone in this prison.

You couldn't do that to him.

So as you pulled the lever down and the ancient engines roared to life, you took a step backwards as if afraid that the entire thing might implode in front of you. "I'm here to stay," you whispered, leaning your head on his shoulder.

He looked down at you in surprise. "The timeline, Sans, what about them?"

You shook your head, recalling the hatred that Sans had felt towards you, for the thousands of times you had slaughtered his brother. Even if the two of you managed to push past your differences, things would never really be the same, would they? Nobody in their right mind would want to spend the rest of their lives with the person who had butchered their family countless times before.

"Someone better..." you explained. "They deserve someone better, someone who could do what I couldn't. Someone... more determined than I was to do good. And when their times is up and they come here and finally free monsterkind, Sans... everyone, they'll have someone." You looked up at G. "And you'll have me."

So as the machines whirred to life and the story continued on without you, you rested your head on G's shoulder, admiring the future that awaited the two of you.

And what could be.

******

Sans took a tentative step forward. The last genocide run, it had felt so different from the rest, hadn't it? When he had struck you down, watched with a sadistic glee as you had slowly bled to death on the floor, he knew that it would be the last time he would ever lay eyes on you.

There were memories on his mind, memories of a twisted timeline, one where he had not quite been himself. But that was only a dream, wasn't it?

He pressed himself against the door that acted as the one and only barrier between Snowden and the Ruins. Whatever decisions a human made in the Ruins, the place where it all started, would determine the fate of the Underground - whether they were to all be freed or condemned to be dragged out of their homes and slaughtered.

Sans shifted uncomfortably, recalling the thousands of times he had watched his brother struck down, human after human after human. It hadn't just been [Y/N] that had lived the same life over and over again, each human that fell was condemned to live through thousands of timelines before the entire system reset and continued on with the story.

The comedian wasn't quite sure what happened when the timelines maxed out and the world decided to do the big grand 'Reset,' but he knew that another human soul would join the ranks of the others stored in Asgore's basement, accompanied with the excuse that they had been collected by the king himself.

The truth was, whatever happened when a human's resets maxed out, they simply died and their soul became just another used for the total seven needed to break the Barrier. It was curious, however, to Sans, that there was absolutely no mention on the whereabouts of [Y/N]'s soul, and to the rest of the Underground, it was like she hadn't existed at all.

What had been so different from the other timelines?

So here he was again, forced to relive through the same sentry duty, condemned to another hundred years of living though his brother's awful spaghetti and murder-feats by whatever poor unsuspecting human would be thrown down here next.

The doors to the Ruins creaked open, Toriel's muffled sobs barely audible. Sans relaxed slightly, calmed by the fact that whatever human were to emerge had decided to take on the pacifist route, as most humans did their first time around.

But what would happen when they got bored?

He pushed such thoughts aside and continued onwards, following the human carefully as they wound their way through the dense forest of Snowden, shuddering slightly at the harsh breezes that whipped by them.

Sans sighed slightly and took a step out as the child approached the gate. Here we go, he thought and extended his hand.

"Don't you know how to greet a new friend?" he asked, forcing a grin onto his face, knowing that he would be repeating this dialogue for god-knows-how-long.

The human turned around to face him, shaking slightly at his presence. They shook his hand once, a weak gesture, before pulling back as if they were about to be struck down.

And Sans would probably be watching them bleed to death in the Judgement Hall in a few resets, wouldn't he?

"The old whoopee cushion in the hand trick," Sans chuckled. "It works every time. I'm Sans, Sans the skeleton. And you might be?"

The human whispered under their breath, so low he could barely make it out.

"Frisk? That's a nice name. I think we're going to get along just fine."