Chainsmoker [ Gaster!Sans x Reader ]

2. Domingo en Fuego

"I don't understand."

You refused to meet his gaze, the knife clutched in your shaking fist. It wasn't that hard, why couldn't you just kill him?! It wasn't like he would die, with a single thought, a single wish, you could bring them all back to life again.

"[Y/N], help me understand."

You had killed Toriel, Papyrus, Undyne, all of them without hesitation. Sure, there had been guilt, but you had buried it, kept moving like a good little soldier. It was simple really. All you had to do was separate Sans' skull from his spinal cord.

"Weren't you happy? Weren't we... wasn't I good enough for you?"

The knife clattered to the floor, the dusted blade shattering in two. Sans was kneeling before you, his jacket shredded from the multiple attempts you had tried to kill him. There was a look of relief in his eyes, though the hatred he felt for you was evident. After all, you had been the one to strike his brother down.

"You don't know what it's like," you hissed, refusing to meet his searching eyes, afraid that if you made eye contact, any self-will you had managed to create would simp,h dissolve. "I've tried, Sans. I've lived the same life over and over again, and it's driving me nuts. I can't do this any more. I just want to... I just want it to be over," you whimpered, feeling much more like a scorned child than a demented serial killer.

You felt Sans' arms wrap around your waist, pulling you closer to him. "It's okay," he murmured, his grip on you tightening. You relaxed for a moment...

Before the bone shot up through the ground and pierced you through the chest.

"Get dunked on you dirty brother killer," he spat, a sneer on his face as he watched the blood pool from your stomach, the life slowly draining out of your eyes. "The [Y/N] I knew, they died a long time ago. You call us the monsters? You're the real monster."

Present Day

You pulled yourself away from the flashback, the guilt becoming too much to bear. You wanted nothing more than to die, to simply become a figment of the monsters' imaginations when they woke up, unaware of the countless times they had been struck down by your knife.

My knife, you thought, the tips of your fingers brushing against the silver blade that was tucked securely underneath your shirt, ready to pull out at a moment's notice. The urge to kill was still there, it was an action that had been carved into your very existence. Even if you somehow managed to overcome your past, live a normal life on the Surface, it would always be there, always to linger in the back of your mind.

"I don't understand," the monster eyed you curiously. You had never seen him before, you were sure of it. Though there was an aura of familiarity around him, an indenting you couldn't quite decipher.

He leaned closer to you, the cigarette dangling in the corner of his mouth. "What exactly are you?"

You swallowed once, wiping your palms against your jeans. He was stronger than any other monster you had faced, the strength of two unified souls. Horror gripped you as you dared utter the name, afraid of the truth that you already knew.

"S-Sans?" You tried the name, playing it on your tongue. For the first time it wasn't just a word, a string of letters that held no value to you. You remembered the Sans that you had... befriended during your first venture.

The skeleton - you were sure of his species - looked at you curiously, his once-bored demeanor vanishing. There were only three skeletons you had known during your time in the Underground, and you were certain that this wasn't Papyrus. Your eyes flickered down to the holes in his hands and you felt your blood run cold.

You had never met the deceased Royal Scientist - Gaster, his name was - but if you managed to look hard enough, there were secrets to be uncovered. "I'm not Gaster," the skeleton droned, his curiosity diminishing. He was back to his stoned attitude, and you felt yourself rather infuriated. You had just met him and already he was more of a child than Papyrus and Undyne combined.

"And I'm not that comedian either," he added after some thought, as if he too was unsure of who he was.

"Then who are you?" you persisted, unsure of how to react. He seemed just as likely to hug you as he would quite literally stab you in the back.

"I'm..." His voice trailed off for a moment. "Call me G."

"G." You cocked your head to one side, unsure of how a letter could possibly be a person's full name. "G as in an abbreviation for Gaster?"

An unlit cigarette dangled from the corner of his mouth. "No pixie stick," he scoffed. "G as in the letter G, the seventh letter of the English alphabet." As he lit the cancer stick you made a face at the puff of smoke blown your way.

"You know those things can cause cancer right?" you pestered. For a brief moment you were you again, memories of the genocides and murders buried underneath your newfound fascination of this skeleton.

"I don't have any lungs," he said slowly, tilting his head to one side as if to examine you better "You're not the brightest firefly, are you?"

You flashed him a sneer before examining the abandoned scenery. It was all too serene, the dusted hallways and plants that were ancient enough to be considered as fossils. "All of this, what happened here?"

G paused, a clouded look spreading across his face, trying to recall memories that were hidden to him. "That I don't know," he murmured and then turned back to face you. "This seems to be an old timeline, most likely the victim of a genocide route to be specific," he muttered, his eyesockets going dark.

You stiffened at the mention of genocide. Moments ago you had been at the brink of killing Sans, taunting him even. But now here you were, the world's biggest lump of self-pity. It suddenly seemed like a lifetime ago.

"You don't remember anything?" you asked curiously, wishing more than anything that this version of Sans retained no memory. Abandoned timeline or not, a fresh start was something you had been longing for a very long time.

Without a word, G stood up and motioned for you to follow him. You winded down the Ruins, nostalgia washing over you as you noticed the trail of dust coating the walls, and the footprints that seemed to eerily match your's.

G stopped in front of a room full of burnt out cigarettes, hundreds, thousands maybe. "Three thousand, nine hundred and sixty-seven," he stated the number as if had been engraved into his mind, and a part of you wondered if it had.

"One cigarette for every genocide run, for every time you killed Sans, and in turn, me," he added coldly, imitating the Sans you had grown to know over the last hundred genocide runs. "I'm not Sans, I'm not Gaster, but I'm still them."

You didn't know how to respond as he took the cigarette out of his mouth and discarded it into the room. He turned to face you, dangling another cancer stick in between his teeth. For the first time you truly saw how broken he was, how desperately he simply wanted everything to end.

He tossed the lighter to you, barely giving you enough time to catch it.

"C'mon [Y/N], let's make it another."