Undertale: Taking The Underverse

Summary:

Side stories, glimpses of the past that had been erased from all but four minds.

The last night before war truly begins.

Sans was laying in the dark of his room when she opened the door. She didn't bother turning on the lights when she closed and relocked it behind Chara and Asriel, or flowey as he was now. The key the punny skeleton gave to her when she offered what she thought was her greatest secret burned a hole around her neck beside the golden heart locket Sans had hand made for her and all of their friends.

She looked into the empty eye sockets, waiting for him to acknowledge their existence, but none came, he was unnaturally still so she knew he was awake. That was fine, she didn't feel much like existing right now anyway.

As she got closer to him, his magic power that for once wasn't locked down tighter than the core itself inside his soul began to dance around in a kaleidoscope of colors. Blue was woven into every stream of flowing magic, however her heart stuttered for a moment as she took her first true look into the streams.

Blue. Integrity. Dedication.

Cyan. Patience. Calm.

Red. Determination. Boundless.

Yellow. Justice. Proud.

Orange. Bravery. Loyalty.

Green. Kindness. Love.

Purple. Perseverance. Compassion.

They were all here. All of Sans was bared to her in this one moment. For her, and her two trembling siblings who are still remembering how to feel properly. She sympathized, after all how long had it been since she'd felt anything but an artificial determined curiosity herself?

Her breath hitched as it passed through her in waves, leaving behind impressions of Sans emotions. His gentle love for his brother, the endless hope for their future together, his own determination to see what came after this to the end. It was suffocating… almost as suffocating as her own DETERMINATION.

She sighed in relief as she took slow steps towards the bed, gently tugging the shaking older girl behind her, respectfully ignoring the tears that dripped down the human girl's rosy cheeks to mix with the white tears of the flower she held.

She was beside the bed when his eyes lit back up. Colors rapidly appeared and disappeared in frenzied flames that poured from his eyes, usually so distant that she couldn't breathe now fixed firmly onto her. Onto them.

They were calm. And warm. And despite himself, inviting. So she dragged her sibling to land onto his chest as she took a seat beside them. The two froze as they were buried into the skeleton's white turtleneck, his jacket laying spread out behind him. His eyes finally left her brown orbs to stare into twin pairs of red eyes frozen in uncertainty. The skeleton allowed his eyes to close with a sigh as he placed one hand around them both, reeling his magic back in to surround his bed. It passed through all four of them as Frisk laid down beside the skeleton and curled herself into his neck to wait.

It took nearly four hours for the two of them to finally relax, and watch as the kaleidoscope of magic whirled gently around them. Pushing against and through them one after another, staring up at the patient skeleton and determined human who laid against one another as if sleeping.

Red eyes met red as Chara finally moved, crawling upward slowly as Sans quietly eyed them, finally allowing himself to move a bit as he breathed, gently rocking them back and forth. She set her little brother onto the skeletal hand that now rested between the human and monster, the flower allowing his roots to unravel from her wrist and wrap around warm bones before allowing himself to fall asleep.

She continued her journey with a determined tilt of her mouth, until she was eye to eye with the arbiter of monster kind, boxing his head to glare straight into his eyes, completely ignoring the laughter of her younger sister beside them.

"When does this end, comedian?"

Frisk… was curious too but had never asked Sans directly. It was always in his offhanded comments after she broke the barrier, so she scooted up to look him in the eye too, and offered her best teary eyed pout.

All she got in return was a snort and a forehead flick that almost knocked her head off his shoulder, and a laugh from her formerly ghostly sibling.

With a quiet sigh, Sans leaned back and snuffed his eye light out. "If you mean this specifically? When you two give in to that thing's call."

Frisk froze, her hands began to shake, her throat dried and from his small off as Chara fell against him again and squished flowey in between them, Her older sister fared just as well as she did.

He gave them a minute to process thankfully, however it only left her with more questions than before. She slowly looked up and saw that Sans' eyes were once more hollow, vacantly staring off into the ceiling. She licked her dry lips and quietly asked, "H-how long?".

A small laugh was their only answer for a time. Long enough for Chara to pull herself back together and once more to silently glare into his unseeing eyes.

"If you mean how long have I known? Always.", was his candid reply, for once not dodging a question with a pun or giving mysterious throwaway answers that confused her. "If you meant how long until this is over?"

He had their attention, no matter what he did, Sans' wouldn't lie to them. Not about this. If there was a way for this to all end, for them to finally have a happy ending…

… She'd do anything to hold onto this moment forever.

"It'll be a while…", before Chara could start screaming, or she had a panic attack at the thought of how much time he was implying, Sans unoccupied hand reached between himself and Frisk to cup the back of her head and slowly press her against his neck. They were all quiet as the two calmed enough to meet his white eye lights.

"If I could end this right now, I'd do just about anything.", the chilling certainty in his eyes matched her own, and startled Chara who jerked her head out of his hand but refused to move from his shoulder. Her siblings were both clingy today huh? She thought to herself distantly as she gazed at the peacefully slumbering flower.

"Let me tell you a story. It started sixteen years ago. You should know the exact date, right Frisk?", sixteen years ago, today, she was born. "A scientist was working on a machine. You see his people had been trapped for quite some time, and he'd become desperate. Desperate enough to risk just about anything really."

…

"The man created a machine he'd built from studying his oldest son's magic. It had the special little ability to open small tears into other timelines, other worlds."

…

"Soon the man discovered that if the holes created could be juuuust a bit bigger, we could travel through them, explore new worlds at the press of a button."

…

"The man was too excited to realize that basing a machine that rips through reality off of a child's unstable magic wasn't such a good idea."

…

"While he gazed across realities, something… monstrous… began to look inside this one."

…

"Eventually it got bored of looking, and wanted in."

…

"The man finally realized what he'd done. Shutting the machine down would erase this world. But destroying it would crack reality as he knew it."

…

"It was an easy choice."

…

"The man shattered across time and space, along with the team of scientists who aided the man in his research. But not before making a promise to his oldest son, left holding his newborn baby brother all alone in a broken lab."

…

" The man promised to close all of the tears he'd opened across time and space, if his son promised to do his best to stop the monstrous being from gaining leverage in their world. With the promise between a father and son made, the man disappeared, from reality and memory, leaving his son an orphan."

…

"I've kept that thing's whispers away from this world for as long as I can remember, kid.", She was faint and pale, her limbs were like lead and she couldn't breathe. The world felt like it was falling apart around her, and she heard it again…

… reset…

… ReSeT…

… ReSeTrEsEtReSeT…

Until air rushed back through her quivering lungs, she was left choking on her own saliva as that thing's whispered died an agonizing death when another wave of Sans' magic burst through them knocking her soul out to meet it desperately. She gasped and shook against his solid and warm form as a hand curled itself into her nape to press her closer.

"And then here you come kiddo, all curiosity and DETERMINATION. You are it's perfect plaything, the best way to explore this world and its endless possibilities without coming through itself. You've already got one spectator on average…", her eyes snapped open again to meet the terrified ruby orbs of her older sister who looked just as bad as she felt with Sans' other hand threaded through her hair. Their eyes trailed to meet the still vacant stare of the skeleton boss monster, whose eye sockets began to fill with red as his eye light burned into existence like ruby coals.

"… what's one more who's even more curious than you are? And doesn't care about what happens in any timeline, as long as it's NEW?", the words left her floundering and terrified, every bit the scared child Toriel always saw when they met in the Ruins.

…

…

…

…

"I promise.", two voices echoed each other.

Sans' eye light burst into many colors again as they locked onto Frisk's own, their determination holding their bodies still as they made their declaration with Chara holding tightly to the skeleton's turtleneck as they silently offered their younger sister their whole support, their own murky black and dark red soul joining Frisk's as they floated in an ocean of Sans' magic.

This was an oath to their friend. Thonky one besides each other and Asriel who would understand and accept them.

An oath to fight back.

An oath to stand their ground.

An oath to wait for the time when they could be free.

It was a pledge to the Royal Judge, keeper of all oaths.

In the skeleton's defense, it only takes a second for him to reply, however that second of his magic going utterly still as it registered the given oaths almost broke her will. It was the small smile he gave as he CLOSED his mouth and pressed his lips to their foreheads one after the other that broke her heart.

"Don't go making promises you can't keep kiddo. I've got one HoPe left, can't go using it on everything that comes my way right?", he didn't believe them. He turned his eyes to something only he could see, allowing his SOUL, nearly three times the size of her own and glowing every color of his magic at once, to appear and rest next to the two humans.

For a moment they were silent, simply watching the two human souls chase after the monster soul as it lazily floated on the current of his magic. Her eyes slowly began to shut of their own accord as his voice rang out once more. "Get some rest, kids. Not much of that going forward, so take all the time you want."

It was the best suggestion gor now, and so Frisk met her sister's eyes one last time, affirming their lromise once more before they both laid back against Sans', allowing his magic to lull them to sleep for the first peaceful rest they'd had since they first fell into the underground and reset all that time ago.

XXXXXXXXXXXX

The door opened once more, after a time. Sans didn't bother to look and continued gazing across the endless timelines and alternate universes forming and disappearing in cycles, after all only five keys existed to his room.

Papyrus was the first to quietly walk into the magically brightened room. Taking a seat in the only chair available, he was followed by Muffet as she crawled onto the ceiling above the bed, forcing the punny skeleton to meet her narrowed eight eyes as she took in the slumbering forms atop him. Undyne was the last through, simply raising the red fin that passed for one of her eyebrows as she locked the door behind her and carelessly flopped down ontot he bed beside the sleeping trio and skeleton.

An exasperated sigh was all Papyrus gave as he leaned back into his chair and snuffed his eye lights out to bask in their elder brother's unrestrained aura for the first time in years. And for a moment all was peaceful, until Muffet opened her mouth to ground out four words:…

…"She's in my spot.", while clawing at the air between her and Frisk who remained oblivious as she snuggled deeper into Sans collarbone.

"Oh, dear.", Papyrus said as his eyes brightened to their normal state so he could stare at the other two monsters Sans had raised on the streets of Snowdin after what Sans' referred to as their biological father's 'accident' that left them both alone.

"Yeah? Well Chara is in mine but do you see me whining?", Undyne snorted, closing her eyes and curling around the 'royal puppy pile' to place her head on top of Sans'.

"Ladies, there's no need to kick up a fuss, if Sans is allowing them to rest with him then I am sure that they require it!", Papyrus interjected with a hand pointed straight up and the other over his soul to express his earnestness.

"I'd look better if I were right there.", Muffet continued as if no one had responded, her claws now snaking their way out of her fingertips as she continued her scratching.

"Oh God, it's gonna be one of those days, isn't it?" Papyrus massaged the area between his two sockets as if to alleviate his suffering. "And let me guess, my dear arachnidian sister! You'd only steal a quarter of a fortune from him in your sleep before making your get away in the middle of the night… leaving a note for Sans to come alone to the middle of nowhere alone with a blanket if he wanted half of it back in exchange for one on one snuggles!?… AGAIN?!"

"No. He keeps his gold in the bank now, you know this Papyrus… I'd have to kidnap you for the exchange.", she finished as if she was saying nothing out of the ordinary.

"Fair enough.", the tall skeleton nodded along before going silent once more.

"Sans.", Undyne spoke out, drawing the two's attention. "What's the call?"

An image, a memory truly, overlapped the world for a moment. Un unchanged Sans held a small sleeping skeleton to his left side as he laid across an old blanket in a musty room filled to the brim with his multi-colored aura. A purple teenage spider monster was glued to his right side, using his shoulder as a pillow while counting a small pile of gold in another pair of her hands. A slightly older blue teenaged fish woman used his chest as a pillow while gently tracing patterns across it with her left hand while her right cradled the small skeleton ever closer. Her right eye had a black slit pupil and yellow sclera, while her right pupil was red and the sclera was light blue. Patience to hold the false construct together, and a single strand of DETERMINATION to give her a way to defend herself even at her lowest.

Undyne the fellow street rat and orphan looked tiredly up at the unwavering form of her older brother and asked, "What's the call?"

Sans broke from the memory in time to catch the small bit of webbing his younger sister allowed to splatter towards Frisk's eyes, turning to catch her eight sets kf wide black eyes challenging him. "What's with the sudden animosity, Spiderbites? I thought you two made up after she bought some of your cakes?"

"We did. Until she took my spot.", was her instant reply, sending two more strands to try to latch onto the young human and remove her. She was intercepted by Papyrus, who reached up to the spider boss monster, gently scooping her off the ceiling and placing her on his elder brother's unoccupied right side. She instinctively chose to bury herself between Sans and his jacket fanned out beneath him with a small hum quickly finding the optimal resting space and passing out. Papyrus leaned back into his chair with a satisfied tilt to his expressionless skeleton face.

Sans sighed as he turned his eyes up, gently rubbing his skull against her throat as she patiently waited for him to respond. He wanted to stay here and just… exist in this time forever. Everything he cared for in one room, his magic out and ready to be used in a moment's notice… why didn't he keep them here again?

A look at the ever tough Undyne's soft eye as she took off her eye patch to show the artificial eye he'd made to help her fight off the gangs back when they'd been stuck on the streets raising Papyrus brought him back to reality. They trusted him too much for him to trap them, to suffocate them with his attention. A mirthless grin made its way past his usual smile as he turned back to the ceiling to consider Undyne's question.

"I need you to promise that you'll remember this Undyne.", she didn't understand, but she agreed anyway, Sans would tell her when she needed to know. "You need to be prepared to face even your worst fears, never let your guard down, little sister."

"My worst fears?", mismatched eyes narrowed onto the older monster at the jab at her age. "You thinking about throwing yourself off a cliff, bonejangle?", his eyes met hers again in a decidedly unimpressed stare as she scoffed and closed her eyes. "Then we'll be fine, big brother." Her last tease echoed her small snort as she too joined Muffet and the Dreemurr siblings in Morpheus' realm.

All that was left awake were the two skeleton brother's, neither of whom desired to end the peaceful quiet. And so the night passed, and the three monsters and two humans rested in peace under the vigilant eyes of the eldest and youngest of the children.

Soon time would be reset, and a war would continue to be waged between a skeleton monster and a formless abomination stuck between worlds using three broken children as its entertainment. All the while two distorted hands reached across time and space, until they curled gently behind the two quiet skeletons standing gaurd and dissolving…

"̭̖͍̮̻̎́̔͆͑͋͛͢͢H̵̡̜̜̝͕̄́̋͑̑̂̒̽̌̚ǫ̴̧̛͇̺̣͉͚̖̯̉́͒́͆͟͡l̵̮̱̝̹̹͐̎̓͑̒d̞̖͍͖͍̻̮͔̋̅͒̅̑͗̓̈̇͢ o̞͚̘͎̬̤̺̼̦̜͌̒̏͛́́̂̍ń̵͇͓̰̯͎͕̟̭͈͒̇̉́̽̚ S̡͙̞̮̰͛͒̇̿̐͜ả̛͙̦̦̹͕̣͛͂̈̚̕n̨̰̳͖͖̯͍̠̑̅̚͝͝ṡ͈͈̳̟͙̉̊̀͞,̛̪̮̯̼̇̾̊̅̈́͟͡ I̷̼̫̪̣̰͈̗̤̟̠͆͋̉͋̔̉͌̓̾͝'̶̟̯̟͍̲͑̋̓͆͆̈̾͞͡m͈̰̠͍͕̫̦̍̎̄̀͡ o̢͔̫̩̗͚͈͆̎̊͋̑͆̋̆̅͠n̢̛̛̮̞̩̺̺̲̣̟̺̒͂́̍̾̆͌͞ m̷̛̫̝̦̆̈̌͢͜͝y̝͔͕̥̝̗̰͗̎̀̍͢͞͡͠ w̴̡̟̬̟͖̳͕̦͐̀̆̓̍̏͆̈́́͡a͕̘̞̰͙̮͈͍̋̓̍̄͐̾͊ͅȳ̧̰̱͈͍͎͎͓́̐͂͆̔ͅ.̧͚̭̠̟̜̳́͂̍͘͜͠ͅ"̶̡͇͓̲̖̞̑́͐̋̉͟͠͡