Chapter 1: The In-Between

Here he was again. Standing in the forever-damned golden hallway, just waiting for the kiddo to show up. Waiting, knowing that he was going to die.

It certainly wasn't the first time.

Hell, it wasn't even under the hundreds at this point.

He turned to the huge windows, admiring the scene with a certain bitter dejection. It really was a beautiful day outside, just as he always claimed. The warm light seemed unfairly bright. So unfairly bright, when he knew what could happen, what would happen—what already had.

After all, the world was going to end.

It certainly wasn't the first time.

The skeleton shook off the familiar pessimistic thoughts. This time… this time would be different. This time he had an idea. A plan that could fix it all, end the damn loop. Sans tugged his jacket closer around himself, warding off a nonexistent chill. Soon. They'd be here soon. He'd gotten pretty good at telling these things.

Sure enough, there's the kiddo's footsteps now. He took a deep (if unnecessary) breath.

It didn't help.

And then… there they were.

Frisk—no, not Frisk, that thing isn't, wasn't, won't ever be Frisk—stopped several paces away. As usual. Their sins, their killing intent, their murderous SOUL filled the very air around the child. Sans could feel it—the strange other that he knew to be Chara—straining towards him, shoving Frisk aside and stealing their control. It was painful seeing them like this, both of them so distorted from who they were. The king and queen's adopted child drained of everything they had been in life, left as nothing but a remorseless villain puppeteering the kiddo Sans loved like family. He had been forced to watch those changes happen, reset after reset. It didn't matter how many times.

He was tired of this.

oh stars, so tired of it all.

"heya. i guess we should get this over with, huh."

The golden light seemed to dim, dark shadows cloaking the hall. Sans was grinning, but there was no joy in the expression. Chara took a step forward and smiled their own not-smile, knife held in a relaxed but eager grip. They took another step. He allowed himself another glance out the window, closing his eyes and only half paying attention to the… thing's approach.

"it's a beautiful day outside."

Chara's foot came down with perhaps a hair too much force: they knew what was coming.

"birds are singing, flowers are blooming…"

The footsteps began to speed up.

"on days like these,"

But more so this day. Now that he had a chance at fixing it. He had planned to stay on script, keep the kiddo from looking too close, but he couldn't help it. Slivers of icy light began coiling in the air around him, pooling at his fingertips.

"kids like you…"

His words were the same, but he could tell that gathering his power was making the other uneasy. That was something new—different, dangerous. He opened his eyes and glared at them, left eye ignited in flickering blue with a foreboding chime.

"Should be burning in hell."

He grasped Chara's SOUL, lifting their body into the air before mercilessly slamming it into the tiled floor. They managed to dodge the bones that materialized after, only to be immediately dragged into the next sequence. More bones on all sides, caging the psycho in as he hurled them down the length of the hallway. Then Gaster Blasters, in front of them, above, below… but of course they managed to dodge enough to remain alive. Sans watched their expression carefully, coldly pleased to see the suspicion he'd inadvertently caused wiped out by the familiarity of this attack pattern.


He gave his spiel about strongest attacks and let Chara take a swing at him. It didn't touch him, of course. A few quick mental calculations told him exactly where the strike would fall and he had plenty of time to step aside. He always loved the look of consternation they got when it happened—it didn't matter how many times they missed, they were always a bit put out by it.

"i'm not gonna' just stand there, you know."

It wasn't exactly what he'd said before, but close enough. There were enough small variations timeline-to-timeline that it shouldn't really matter. They survived for a while longer this time: wisely ignoring his offer of forgiveness but still dying in the onslaught of rapidly shifting attack types. He couldn't ease up, but he needed them to get farther, to get to the last attack. It was the only time his plan had the slightest chance of working. But for now their body died, the SOUL shattered… and then he was standing a few minutes in the past, again waiting and admiring the beautifully lit hall.

And again he heard those tell-tale footsteps, closed his eyes (managed not to get all glow-y this time), gave his lines, and launched into the attack.

They got closer, but weren't quite quick enough when surrounded by blasters. They shattered.

The fight began again.

And again.

And again.

Sometimes Sans had to wonder if even they couldn't remember everything—couldn't recall enough of all the other time's they'd fought him to gain an immediate advantage. Maybe some of it blurred together; he could say from experience that all the repetition and lifetimes worth of extra memories tended to overlap. It's not like he could easily keep track, having lost count somewhere in the mid-hundreds. He was reasonably sure Chara remembered more than Frisk, but sometimes… well, he wondered. He certainly wasn't just gonna walk up and straight-up admit to knowing timelines. Hints were as far as he went on that front.

He absentmindedly dodged another slash, sending out a barrage of bones that the thing began frantically dodging. Summoned blasters began firing pure magical energy in their direction. They spun out of the way, landing just where he knew they would.

It was now or never.

His eye flashed as he caught their SOUL and flung them through the air, slamming their body into the floor, ceiling, walls, columns. As his onslaught slowed, he CHECKED Chara's HP, relieved to see it sitting firmly at 1. Same as his own.

this has to work.

He let the thing's body drift back to the ground, releasing his hold on the SOUL. Chara's face lit up with demonic glee, expecting the end to come as easily now as it always had. Sans's lines came effortlessly, burned into his memory as they were, and then he waited. They had always been an impatient sort, so when they tried to get a stab in early he just caught them and pushed them back. He let his shoulders droop slightly, trying not to let fatigue catch up to him while simultaneously pretending it did.

This would be the tricky part. His plan depended on it.

He just needed to die… but not die.

Be killed… but not killed.

And, on top of it all, he had to die-not-die at the exact same moment they did.

He spread his senses—magical and otherwise—and let his eye sockets slide shut.

A few SOUL-beats passed.

They began slowly making their way forward, careful step after careful step. He forced himself to stay relaxed.

They raised their knife high and Sans could all but see their murderous smile.

The knife came down in a red arc.

He dodged the first strike easily, almost literally in his sleep. "heh, didja really think you would be able—"

Sans blocked their second strike with a small blaster, having it bite down on their wrist until the knife clattered to the floor. He kicked it aside.

"not this time, Chara." They tensed when he spoke their name, not expecting it. "i have a better idea."

His eye lit with magic as he grabbed their SOUL, simultaneously calling out his own. Even caught is the grip of his magic, Chara's SOUL—or Frisk's, technically—was vibrantly colored: a splotchy mess of harsh blood and hearth-warm red. His own was silvery gray, uniquely opalescent as blue and gold lights danced under its surface. The two hearts beat softly in the air between them, and he was somewhat gratified to see real fear glimmering in the thing's red eyes.


"time to QUIT, kiddo."

Sans dispelled the blaster biting their arm but they remained frozen in place, barely able to move. They squirmed, trying desperately to lash out at him. He let his own SOUL drift down to settle on the floor as he summoned another blaster directly overhead, aimed down at both of them.

Chara chuckled their dark, distorted laugh, the fear he had glimpsed earlier seemingly forgotten. "Oh, I didn't know you were so eager to die. That'll hit us both, Sansy."

Sans smiled back and they winced as he wrenched their SOUL unwillingly to the ground. "uhh, that's kinda' the point."

Confusion flickered in their red eyes.

Magical energy built up in the Gaster Blaster's maw, light sparking through its closed teeth. He hoped to the stars there would be enough power to sustain the blast after their bodies were destroyed, enough to obliterate the SOULs as well. No matter: it was time to put theory to the test.

"welp. see ya on the other side."

Confusion became an instant of shock and disbelief—wiped out by a swath of crackling blue-white energy.


Everything went black as, at the same time, both SOULs shattered.


Then, Chara laughed.

And laughed and laughed and laughed as the void echoed.

For a moment they had been… they had been scared. Scared of Sansy!

How thrilling!

And— and— and! He knew them! Chara! Their name!

He called them by name.

Oh, they had always suspected that Sans could remember. Suspected that he was at least somewhat aware of the timelines reseting. But this? This was beyond their wildest hopes.

Sans knew—not guessed, but actually knew—what happens to everything when they finally beat him. They never did get to see him die, never saw him finally collapse into a pile of beautiful dust. He must have watched at least once. Watched until the end.

And then, he remembered.

Somehow, he had always remembered. Come reset or total obliteration.

How thrilling!

Just think how much more fun it would be, after all. Tormenting someone who would remember.

It sent eager shivers down their spine.

The void yawned around them, empty and vast and pitch-black. With another echoing chuckle, Chara summoned their determination. It lit up the air around them before condensing into two glowing orange options: RESET or CONTINUE. As if they even need to think twice.

They reached for CONTINUE.

They stopped.

They… stopped?

Then Chara noticed the faint tinge of blue on their skin. When they glanced down, their SOUL was gripped in a familiar light. Their breath caught.

"let's see if i can make a difference now, kiddo."

He wrenched them away from the pair of floating icons, spinning them roughly around so that he could see their SOUL. All it took was a glance to confirm his second hopeful theory. Here, deep in the black void between timelines, it was clear that Chara's SOUL was not entirely their own. The warm red light leaking out through the staining cracks of the other's influence was everything Chara had lost: compassion, joy, mercy, friendship. It was shining weakly but with determination. Frisk was in there, somewhere.

Sans could get them back, and through them, hopefully… everything could be fixed.

The power surging from his SOUL lit his eye with a glow fiercer and more driven than Chara had ever seen before. They managed to break his hold with a determined shove, but they were shaken. Badly shaken. Red eyes met lone burning blue—Chara's grip on their knife became painfully white-knuckled as they tried to stop shaking.

"H-hah-a…" It was an uneasy laugh, more for their own benefit than anything else. "A d-difference? As i-if. What are you gonna' do, try to keep me from CONTINUING or RESETTING f-for the rest of eternity?"

Sans said nothing, but the intelligent glint in his eye sent another shudder of apprehension down their spine. He sent a wave of bones in their direction, trying to catch them off guard again.

"That won't solve anything, Sans." They spat out his name with vindictive pleasure. "Fighting forever? Like a lazybones like you could even keep it up for an hour."

"you have a point. with ulna this work, i'm already feeling pretty bone tired." He shrugged, winking his unlit eye in that way that never failed to infuriate them. His puns were rewarded with an annoyed hiss and a slightly more reckless lunge. The knife-tip missed his ribcage by a hair, snagging and cutting off a piece of his jacket's zipper before he teleported out of the way.

He didn't teleport far.

In fact, he flickered back into existence directly to Chara's left, slipping inside their guard. Reaching with both his magic and his hand, Sans slammed his boney palm into the stained SOUL.

Frisk was blasted away, skidding to a stop just a few feet away from the floating icons. Wisps of color, red and blue, drifted briefly in the area around the small human before silently disintegrating. They pushed themselves upright, disoriented and confused.

Chara was caught, trapped as nothing more than a wraith of twisting red lights centered around the shattered remnants of their own SOUL. For a moment they just stared: stared at Sans, at his magic wrapped around every shard of their SOUL, the void, at the icons that seemed to taunt them, and at the human child who stared back with wonder and the slightest flicker of rebellious hope.

"S-sans?" Frisk held up one hand then the other, fascinated and disbelieving, unshed tears shimmering in the corners of their eyes. They were stuttering worse than Alphys on a bad day. "A-are y-you real? I-is this… r-r-real?"

"yeah, kiddo. don't worry, i'm here."

"I… I-I…" Frisk tried not to cry, tried to take a shuddering breath, tried to calm themselves down, but they couldn't stop. They wiped at their eyes in a futile attempt to push the tears away, but they kept coming. The sound of Sans's voice was just… just so… caring. So concerned for them and they didn't deserve it, didn't deserve forgiveness, not after what they let happen. "I-I'm s-so s-s-sorry, Sans."

Chara sneered, parroting Frisk's words under their breath in a high mocking tone before harshly shouting, "As if he'd ever forgive you!"

The skeleton tightened his magical grip and Chara's ghostly outline flickered, glitching under the strain. "i think tha—" he grunted as they began struggling against his hold, "—that's up to me, Chara."

The child stood up, still slightly unsteady but eyes glinting with determination. "After everything, I-I didn't think I would ever even h-have a chance. I don't deserve it, but I'll d-do anything to try to."

Sans grinned, a bit more genuine than he'd been able to manage for quite some time. That's the most he'd ever heard Frisk say all at once. And wow—just hearing Frisk's voice free of eerie, foreboding overtones was more of a relief than he had expected. They could still be saved, even if Chara was too far gone. Frisk could still be the same kid that he'd watched over and welcomed into his family all those resets ago, who he'd taken to seeing as another younger sibling.


Frisk nodded, resolute.


That was apparently one of the few things neither broken nor whole human had expected. Chara froze as Frisk glanced between the icon and Sans, not sure they'd heard correctly.

"throw me a bone, kid, trust me on this one. i'll keep the psycho parasite here so you'll be the only one going back."

"The only one…? But—"

He knew. For this to work he'd have to stay behind. "hey, somebody's gotta' keep an eye on this thing… i guess an eye-socket from a nobody like me will have to do." Nothing like bad jokes to try to lighten a depressing situation. It always worked. Most of the time. Sometimes.

Frisk made an odd sound, like a sort of hiccoughing laugh stuck in a whimper. "Sans…"

"trust me."

A single nod, and then Frisk just stared at Sans for a few seconds, memorizing everything about him that they could. They reached a shaky hand toward RESET. Chara redoubled their escape efforts, red eyes wide and frantic.

"uh, hey. before you go," Frisk paused with their hand flat on the now-yellow icon, and Sans could see fresh tears in their eyes. "do you think you could maybe, you know… tell paps—"

The kid stopped him with a small smile. "Sure… but I'll get you back." They were determined to. "I promise."

Chara screeched for them to stop as they thrashed about as much as possible, desperate and angry and scared.

Frisk's hand slid off RESET and they vanished.

Sans summoned a blaster.

The pair of icons remained for a heartbeat before he completely obliterated them in a blast of magic, sending a shockwave thundering through the very essence of the void. Ripples of shadows and contrast swept past him, somehow a movement of everything and nothing all at once. Maybe it should be frightening to be standing at the center of such a maelstrom of power, at the mercy of the void, but somehow Sans felt unconcerned. After all, it had a different target.

Chara was ripped away. The shard remnants of their SOUL were utterly destroyed, and they died with an expression of shock in their eyes. No more fear. No more hate. Some part of them looked almost relieved.

And then everything fell still.

Sans was alone.

He fell to his knees, exhausted. It was over. Finally.

His eye sockets slid shut.

"good luck, kiddo."


It wasn't really what Sirius had expected.

Death, that is.

There had been a moment of shock, fear, regret… and then everything went black. He had heard Harry desperately calling for him as he fell, pulled into the void. A cool wash of magic flowed over his senses, soothing him, even as he felt his soul distantly shatter.

Now he was just floating in a vast nothingness. You know: dead.

Woo, yay.

He didn't know how long he let himself drift—and he seriously doubted that it really mattered—until he eventually realized that he could actually move. Sirius couldn't see the ground he was now standing on because, as previously observed, literally everything was black. Turns out the infinite expanse of abysmal emptiness that comes after death wasn't a particularly scenic place. Fascinating. It didn't look like exploring his new surroundings would be very interesting, but there wasn't really anything else to do.

It was another indeterminate amount of time before he actually found something.

Or rather, something found him.

"how did you get here?"

The voice was unexpected, low and threatening and coming from directly behind. He wanted to whirl around wand drawn, but found himself unable to move at all. "I… uhm… died? Is that not usually how people end up in the afterlife?"

Whoever had that voice gave a surprised laugh and remarked, "i think there'd be more people here if this was the afterlife."

"You make a good point, mysterious-voice-who-has-me-hostage-somehow. So where am I?"

"i'd call it 'purr-gatory', but i'm not kitten around when i say that's not completely true."

Sirius was beginning to question his sanity. "Wait, were those puns?"

"not to be catty, but i thought they were obvious."

"Merlin's pants, they were!" Now it was his turn to laugh, and it felt so good to laugh again after who knows how long he had spent wandering alone in silence. It took him a moment to come up with a suitable response. "Laughter really is the best medicine, 'cause I'm feline better already!"

Whoever it was chuckled again and, without missing a beat, replied, "too bad good jokes are pretty much im-paw-sible to find here in the void."

The power that was keeping him immobile loosened slightly as whoever-it-was relaxed a bit. His feet regained contact with the void ground and he decided it was high time to introduce himself. "I'm Sirius."

"nice to meet 'cha and all, but you don't really seem like the serious sort."

Sirius blinked, grinned, then found himself laughing again. "Got it in one, whoever-you-are."

"the name's sans. sans the skeleton."

Author's Note:

Disclaimer: I do not own Harry Potter or Undertale.

And so it begins!
I'll try to update this fanfiction on the first of every month. In the mean time, feel free to write reviews with what you think so far, questions, or ideas (or pointing out mistakes, that'd be helpful)!

See ya on the flipside, everyone!