Title: Genocide's Last Whisper

Sans stared at his brother's empty bed. It was cold. Cold like the rest of their house, since Papyrus wasn't around to keep the furnace running.

"I'm going after him," Sans said. He pulled on his boots and tugged a hooded jacket over his blue sweater. Normally, he'd just go in his slippers and coat; teleportation was so much more convenient than walking out in the snow.

But Papyrus didn't have that luxury. He had to walk everywhere with that overstuffed backpack of his. And now he was setting off on foot in a blizzard to confront someone—someone who could kill him.

Sans had tried explaining it all before Paps left, but there was no getting through to him. As headstrong as ever. Sans didn't know how Papyrus always managed to be so hopeful, even when everything seemed hopeless around them.

But hope wasn't going to save him from this fight with Frisk.

"Promise me you won't interfere," he'd said before leaving.

As if Sans could promise that! Of course he would step in if Frisk tried anything against Papyrus. But what could he do? He wasn't much for fighting himself, and the one person who would've been able to help…

He squashed down that thought, along with a pang of sadness and guilt as he closed the door behind him. No time for regrets right now, or for dwelling on what might've been.

The wind whistled in Sans' ear sockets as he made his way through Snowdin Forest towards Waterfall, following fresh tracks in the snow where a small skeleton had passed not long ago.

By now, the tracks were half covered by drifting snowflakes; Sans had never seen such a bad blizzard here before. But then again...a lot of things were different lately.

Frisk...

Sans clenched his bony fists in his pockets. How had they changed so much since that first encounter on the way to the Ruins? They'd been so nervous and full of questions, like any human who stumbles into the Underground.

And Sans...he hadn't known about their plan to free all the monsters from this place, where they'd been trapped for centuries. He didn't know anything about resets or timelines—how could he have? He was just a lazybones who told jokes and slept on his brother's couch.

But everything changed after that date with Papyrus. It went well, better than Sans ever expected it would. Papyrus came home floating on cloud nine, bubbling over with happiness as he recounted every detail—the spaghetti dinner, the romantic stroll by the river, even the goodnight kiss under a streetlamp.

Sans couldn't remember when he'd last seen Paps so happy; it warmed something inside him that felt like...

But then Frisk reset.

Papyrus forgot about them completely—or at least acted like he did. But Sans knew better; he could see it in his brother's eyes and hear it in his voice whenever their conversation veered close to that missing piece of time.

Frisk was doing some kind of weird time magic—and lying to Papyrus about it! That made Sans "mad," as humans say. And scared for his brother's heart, because if Frisk could just erase parts of his memory like they were scribbling out lines in a notebook...

Had they done that before? To other people?

It seemed likely. The more Sans watched them—their determined expression as they fought through monster after monster to get to Asgore and break the barrier between worlds—the more convinced he became that Frisk wasn't really a kid.

They were too smart, too talented. Too ruthless.

"ha...you're gonna have a bad time."

Sans paused in his tracks. The echo of those words rattled through him like a chill wind. What had Papyrus said? "You've caused so much pain to everyone I care about...I won't let you hurt them anymore!"

Was he going after Frisk to protect them all from more Resets? And what if he succeeded?

Sans shuddered. Their last fight...the one where they were evenly matched, dodging and teleporting and attacking with all their might...and then Sans saw his brother's magic fade, his strength waver...

He didn't want to remember the feel of Papyrus' skull in his hands as he tried to keep him from collapsing onto that cold corridor floor.

"no..."

Sans tightened his grip on the jacket around him. If Frisk...

But then again, maybe it was for the best.

Sans closed his eyes and let out a shaking sigh.

Papyrus wasn't well. He hadn't been since that first day when Asgore absorbed the other souls and transformed into some kind of nightmare king, stronger and more terrifying than anyone Sans had ever fought before.

Papyrus had used every ounce of strength he had—and then some—in that final battle against Asgore. And while he'd managed to hold him off long enough for Frisk's mercy button to finally be within reach, it came at a terrible cost.

A cost Sans couldn't heal away, no matter how many times he reset

Papyrus was dying.

Slowly, painfully—his bones growing brittle, his soul flickering like a dying ember.