Please feel free to point out anything I might have messed up. Chapters will be added as soon as they are finished and edited. Thank you!

Note: I do not own any of the characters, places, etc from Undertale in this story. Toby Fox owns Undertale.

Chapter 1

The red eyed kid was laughing. Sans initial attacks had quickly brought them down to 1HP but now nothing was landing. Attack after attack, they dodged deftly. With each bone narrowly missing, the laughter had grown louder. It became a thousand laughs as it echoed and slammed into Sans.

"Kids like you should be burning in hell!" Sans sent out his blasters.

They hit. The kid stopped laughing as the maniacal grin momentarily slipped from their face.

Smiling again, they whispered at the skeleton. "See you there…"

They collapsed. A blood red soul floated out from the striped sweater. It calmly bobbed a few inches above the corpse.

Sans had seen this human's soul many times already. He had killed the kid a few times but they would soon come back. He always felt guilty seeing the soul. It represented all the pain and evil possible in the world yet a nagging thought always invaded him. The kid could have been good, a friend even. No. He would shake his head. This soul meant an ever living death.

So Sans waited. He knew it was only a matter of time before the corpse erupted into life again. It would charge him in a matter of seconds after returning. No love lost between them. To pass time he took out a ketchup bottle from his jacket.

"To Papyrus," he downed half the bottle in one swig.

Examining the bottle, he sighed. Papyrus had never been a fan of ketchup. When Sans tried to convince him it was a form of spaghetti sauce, he had scoffed. If nothing else Papyrus knew his spaghetti.

Looking back at the soul, Sans smiled. The soul seemed even less like that kid than it had before. Sans couldn't help but see it as spaghetti sauce colored now. Slowly, he approached it.

Kneeling next to the corpse, Sans saw various cuts on the human. He pulled the knife from their hands. They really were a small human. Heck, they were small enough for him to easily pick up like he used to do with Papyrus.

Brushing the thought away, he noticed blood dripping from their left hand. Adjusting them slightly, he could clearly see a gash. The hand was an odd greyish color but that wasn't what interested Sans. The hand had been mangled to the point of exposing broken bones.

"Heh guess the kid wanted lend a hand." Sans chuckled, half expecting to hear Papyrus groan.

Staring at the body again, Sans felt impatient. How long had they laid like that? It felt like an eternity. He yanked their body so it sat up. The soul flew onto the floor and skidded leaving a red trail in its place. Shocked, Sans chased after it. The colors swirled inside, a mix of scarlet and maroon.

Carefully cradling the soul, Sans returned to the body. Gently, he brought it back to the center of the kid's chest. Letting go, it dropped.

Sans was horrified. Souls could reattach if the body hadn't dusted yet. Again he brought it up. It dropped.

Sans anxiously scooped up the fallen soul. He searched for any cracks or damage to its being. Nothing! He sighed, relieved. It could still return to the body.

It didn't. No matter how Sans tried to force the soul back, it refused. Frustrated, he laid the kid back down and put the soul on them. No longer bobbing slightly away, it sat firmly where it was placed with no indication of reattaching. Sans became painfully aware of how cold the kid's body was. He wished Alphys was here. She would know exactly how to reattach a soul to a body. She'd done it before but Sans knew she wouldn't be able to help. She was dead.

This brat had killed everyone. The kid had appeared and monsters had begun disappearing. Papyrus had tried to stop them. He reasoned they just needed a friend. Someone needed to show them how to be good.

Sans began to rock thinking of it. He had chased after Papyrus to protect him. He arrived to dust in the snow. The kid stared at him, smiling.

"Don't worry! I've got something special in mind for you." They had laughed before running off.

That awful laugh. Sans swore he could hear it now just thinking of the kid. It was the same laugh as they dusted everyone.

Sans recalled rushing to Asgore. He had begged for him to intervene before the kid got through the entire underground. Save the few monsters that hadn't died yet. A life underground was better than no life at all. Wasn't it?

A chilling realization hit Sans. There was literally no one left but him. Asgore had been dusted for all to see. One after another, the kid had left only him. He had waited here. He was the last thing between them and every living thing above.

Sans felt ill. If he had truly eliminated the brat, then no monster would ever leave the underground. It would be their permanent fate. There would be no more resets. There would be no more Grillby, Alphys, or Undyne. There would be no more Asgore or Royal Guard. There would be no more Papyrus.

"HEY KID! I got a bone to pick with you!" Sans yelled. "You better get back here and face me!"

The soul sat on their body.

"You can't just leave! You aren't done yet!"

He yelled until his voice was hoarse. What could he do? It was just him, stuck in the underground alone. What was the point in getting out without the others?

His voice cracked as he began screaming. "You can't do this! Come back!"

He was wailing now but he couldn't stop it.

"Please! Don't leave me here. Kill me! I won't dodge just come back. I can't live like this! Please don't leave me."

Blackness surrounded Sans as he cried out. He begged. He begged the kid to live again. He begged to be spared this one time and let to die. He begged for Papyrus.

But nobody came.