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The humans dusty knife slides through Sans' chest, the wound familiarly painful. His shirt is torn around a gash, crimson soaking through white, bubbling through his teeth with a ragged gasp in. He stumbles back, bunching fabric up in skeletal fingers.
Sickening deja vu makes his head spin, yellows and blues and pinks blurring together. This scene feels all too familiar to him. Everything, for a long time, has felt too familiar to Sans.
Does that mark his theory true? He wonders silently to himself. He's been watching this human for awhile, marking down their oddities, taking note of every bit of familiarity. The way they strolled so leisurely through the Underground, how they dodged his attacks in such a easy fashion, the way they seemed to anticipate what he'd do and say, this strange deja vu. He thinks it all has to amount to something.
This human—if they even are one anymore—can control time.
Or, that's Sans' working theory.
Blood bubbles theatrically from between his teeth and his knees shake beneath him. Threatening to buckle underneath his weight or patella's beginning to dust?
His eye lights drag up to the kid. They stand still, bathed in the red light of their own soul. There is nothing on their face, in closed eyes and a mouth pressed into a thin-line.
"So…" Sans finally breaks the silence of the hall, "guess that's it, huh?"
The human in silent and Sans laughs, a wheezy sound that passes through the taste of dusty iron. This all feels like one big joke. Fighting against a kid who can control time, fighting so they won't just go back in time and do this over and over and over again with a version of himself who won't remember.
Papyrus, Undyne, that lady he knows but doesn't. What had been the point. What had everyone died for? What has he been fighting for?
"Just-" he knows what he's going to say before the thought even enters his mind, "-don't say-" the words taste like awful defeat in his mouth, like giving up, "I didn't warn you."
When Sans closes his eyes he sees his brother. A goofy smile lighting up his face as he hunches over the stove. Undyne clapping him on the back while helping him with his training. He hears that lady's fluttery laughter, feels the door pressing into his back and snow soaking into his shorts.
When he opens his eyes it is to blurry vision and an all-consuming red light. The human's soul is bright as it floats in the space between them. The source of their powers, of Sans' suffering, of all of their suffering. It is what monsters lack, what makes a human so powerful.
Determination, the will to keep living. An unstoppable force. It is something fit for a God.
Sans isn't stupid, he was a scientist once after all. He knows- he's always known he can't win against this creature, this God. If he kills them then they go back, and they go back, and they go back. And they kill him. For good. But when he closes his eyes, he sees his brother.
His magic sparks to life with a step forward. A flash of blue light and he is in front of the human's soul. Their expression is unchanging even as bony fingers close around the culmination of their being.
Red squirms in his grip but he doesn't let up, pressing down into the center of the soul, squeezing and ripping and tearing. Blinking rapidly through blurry vision and wheezy breaths as images of his brother and friends burn into his magic. The human is a motionless husk, knife loose in their grip. And then there is a shatter.
*but it refused
There is a pop loud in his ears and his vision fills with a searing red. Beneath his feet the ground shatters and ruptures, their earthen sky cracking to reveal faint streams of light. The scream he lets out is guttural, something that is not quite magic flooding his system. It wraps around his soul in a vice like grip, invading it. It spreads throughout his magic, his bones, until he is new.
A monsters soul shatters after they die. But humans hold determination, giving them the power to persist after death. Once the humans feared this, for after a human died they could absorb their soul. And when a monster absorbs a humans soul, they become a beast with unfathomable power.
*Ow? What the hell man?
Sans coughs up something that is not quite blood, the red too bright against the yellow tiles. He stumbles in pretty pink shoes, in frilly blue skirts that tickle his knees. His souls beats hard in his chest, a continuous thumping in his ribcage growing rhythmically louder and louder. He presses a hand to his chest, finding a gorey slash of blood staining blue frills. The blood feels as though it has long since dried, crusted and flakey yet it stains his hand anyway.
His other hand closes around what he finds to be a staff. It is pink and cute, presenting itself with two sets of fluffy red wings. Encased inside of it's top is a heart- no. Encased inside of the staff is a soul. The humans soul.
Sans wraps a second hand around the staff and feels it pulse with determination. Raw power flows through his bones, his magic, his soul, and he basks in a power so potent he can nearly taste it.
His eyes leave the soul after a long moment, slowly drawn up to the kid. He sees the human in a new light for once. No longer a God they sit trembling in fallen dirt and stone, mumbling incompressible words as they raise their hands above their head.
Sans takes one slow step forward and then another. The ceiling shakes above him, golden pillars creaking and splintering beneath it's wake. He steps in patches of faint light, legs held together by determination keeping him up.
There is an odd expression on the humans face as they look up to him. Confusion, hope, horror. A mix of the three or something different all together.
"Sorry, kid," Sans says the words with a chuckle, raising the staff high above his head.
"Wait-!" The human gasps, coughing and choking on dirt and dust that floats through the air, "Sans-"
Power radiates through his arms as wings flap, his smile widens. "Get dunked on."
*Stop!
"I didn't do it!"
Two voices nearly too similar to pick apart overlap before the soul gives a violent shake. The staff turns burning hot in his hands, red a blinding light, determination nauseating in his stomach. It is a blast of pure determination that kicks up a cloud of dirt and dust, makes the ground tremble beneath his feet and ceiling rumble. He blinks and coughs as everything settles, staring down at the smear of red with heaving breaths.
The human is dead.
Falling stones count down the seconds he stares at the stain of blood, marking how long he stews in his confusion and disbelief. How long he waits for time to reset. But it never does. The human is dead and time remains the same. Because he stole their soul, because he stole their powers.
*Dumb ass
A voice hisses, the sound seeming to echo around the hollow of his chest. He gasps, pulling the staff to his chest in defense as his eyes dart around. The wings on the staff hit his chin as they give a flutter and it jerks sharply up in his grasp. It takes him just an inch off of the ground before he pulls it and himself back down, casting a wide-eyed look at the encased soul. It's talking to him. The soul, it's alive on its own?
The soul screams it's frustration and Sans hisses in pain. It's wings flair open and close, crimson glistening in streams of light as more dirt falls around him, Judgment hall slowly caving in around him.
*Why would you- I can't-
"Kid?" He cuts the staffs rambling off in a trembling voice, fingers dinging hard into his palms as he holds the staff in a vice like grip.
The staff is silent for a moment, and somehow Sans can feel its rage. Prickles of a searing hot pain that shoots up his spine.
*You think I'm your little friend? The one you just murdered?
Each word is spoken slowly, white hot rage seeping into it's tone and Sans matches it with a hard tone of his own, "Then what are you?"
The staff's laugher sounds cruel, devoid of any humor.
*What do you think I am? Take a look at me!
He holds it at length as four great wings spread out wide, red feathers on display, "Well you look like the kids soul."
*I am the one controlling their soul. The God of your world. Now release me!
"What?" The staff darts at him, pushing against his outstretched arms that hold it at bay. Wings flutter at him, hitting his shoulders repeatedly, "Stop that- what do you- what do mean controlling them?"
Magical sweat trickles down his brow and he tries not to show his nerves. This thing, it has to be lying. It couldn't have been controlling them. Because if it was then the kid was innocent. And if the kid was innocent…
*You know what I mean.
"You're lying."
*I am a lot of things, but I am not a liar. Sans.
If the kid is innocent, then what did he kill them for? Sans' head jerks towards the smear of blood, nothing else left of the human. Not even a body to bury. Two steps taken towards their remains and he stops. The human was innocent, controlled by an evil deity. He just killed some kid. He curses under his breath. What is he supposed to do?
*RESET
"What?" He hisses the word out, looking down to the staff.
*RESET now. Do it now. You want to help Frisk? RESET.
"You-" He swallows and stops. RESET, is that the power to control time? "Will that help? Will that bring the kid back? Everyone you killed?"
The staff lets out a low hiss.
*RESET, it's the only thing we can do. RESET. RESET. RESET.
Sans hesitates for just a moment before giving in, "How do-"
He's cut off by the staff. It rips himself free of his left hand, guiding his other hand in a wide arch. A button appears in it's wake, black with the single word RESET written on it.
He raises a hand and pulls it back, "What will this do?"
*For the love of- just press the damn button!
The staff launches itself down hard, cracking open the tiled floor. The cavern trembles above him, rocks tumbling and splitting as they hit the floor. Sunlight seems to falls as he reaches for the button, dirt clogging his naval.
"Fine." He says in a quiet murmur, closing his hand into a fist and hitting the button hard.
Determination burns him from the inside out, hot and sudden. The staff disappears from his hand, wrapping around his soul, becoming it, as the world is pulled from underneath his feet. He chokes on the absence of air. He dies and he is reborn.
Sans opens his eyes and he is home.