AN: Hey there and welcome to my second Undertale fanfiction. This is going to start off really dark but I promise the next chapter will be much happier as will the others that come after it. There will be elements of hurt/comfort and angst throughout but it will have many more fluffy and happy times to make up for it. This fic will most likely have shorter chapters and will be told through a series of connected one-shots following the lives of the main characters. I hope you'll enjoy this story and please let me know what you think by leaving a review! Thanks so much :)

Disclaimer: Toby Fox owns Undertale, not me. I only own the plot of the stories I write.

Sans lingered outside the ruin doors like he did every other timeline, waiting patiently for the human to appear. Whether it would be Frisk or Chara he had no idea... he only hoped it would be a good loop and he wouldn't be forced to watch his brother and friends die once again. By his calculations, it would still be about half an hour before the child emerged so he had some time to spare.

'Welp, might as well get comfortable.' He thought to himself, teleporting into the branches of one of the trees so he had a good view of the path. 'I know I'm probably hoping for a miracle here but... please let this be the last time.'

The short monster had lost track of how many resets had occurred, causing him to relive these same days over and over, and he knew that if it weren't for the ones he cared about he would have given up long ago. Yet even after all this time he kept holding onto the hope of a brighter future, one where they were free of the loops, one where he managed to save Frisk from the demon that possessed her. He'd known since the first so called 'genocide loop' that an evil presence had somehow managed to latch onto the tiny girl, corrupting her pure soul and tainting it with darkness. Sans had realized this as he stood in the judgment hall, blinded by rage at the merciless slaughter of his brother, as he pummeled the brat who had caused him so much pain. Looking down at the broken body of the child he was about to kill, the comedian was shocked to find a pair of chocolate brown eyes staring up at him with tears building in the corners as if trying to say they were sorry. Before he was able to respond, however, they were replaced with the venomous red that he had grown so accustomed to. The kid had launched herself at him and he reacted without thinking... sending a bone flying straight through the red heart that made up her soul. The next thing he knew, he was waking up in his room back in Snowdin.

'Poor girl...' He sighed, glancing up at the cavern roof. 'Frisk's only ten, she shouldn't have to deal with this crap! That Chara brat is gonna have a bad time for messing with my kid."

The jokesters eye sockets widened in surprise as realization dawned. "Whoa, what did I just..."

He was drawn from his thoughts as the ruin doors creaked open and he caught a glimpse of a striped shirt stepping through the exit. The kid paused, glancing around, and Sans teleported to the forest floor... hiding behind a tree to stay out of sight.

'I didn't see any dust covering her...' The hoodie clad skeleton pondered, risking a glance in the girls direction... a wide grin appearing on his face as he watched the child discreetly searching the woods with her brown eyes. 'Nope, that's definitely Frisk.'

He watched as the girl made her way toward the bridge, chuckling silently when she whipped around with a slightly annoyed look on her face after he broke the stick. It was a game of sorts. Sans would try to creep up on her while she tried her hardest to catch him in the act... so far it was all for 0 in his favor.

"Human, don't you know how to..." The small skeleton began once he'd caught up to the girl, only to be cut off as Frisk turned and latched onto him in a tight embrace. "Heh, what's wrong buddy? Did ya miss me or something?"

"Sans... I can't take this anymore." She whispered, tears rolling down her face as she tried to control her crying. He, in turn, gently wrapped his arms around her tiny form... noticing how the childs entire body trembled from her sobs. "I don't want to keep hurting our friends... I don't want to hurt anyone!"

"Shh, I know kiddo... I know." He soothed, running a bony hand gently through her hair. "I'm sure we'll figure it out if we keep trying. Hang in there, okay."

The human just held on tighter, looking as if the world were about to end as she clung to his hoodie. They stood there, taking comfort in each other for what seemed like hours, and Sans was undeniably relieved that he had managed to convince Papyrus to train with Undyne today instead of recalibrating his puzzles. Finally the distraught little girl looked up, whipping her face on her sleeve in the process.

"It's just..." She spoke at last, pausing to figure out how to say what it was she wanted to say. "It's just that I've tried so hard. Each time we make it to the surface I feel like it's finally the end but then... Chara forces me to reset. I can't fight her Sans... as soon as we reach the surface it's as if all the determination I had just disappears and leaves me helpless to her influence."

The comedians eyes turned dark upon hearing how that demonic brat had been tormenting the child he cared so much for. He had known there was a reason behind those resets, after all, why would the kid trigger them when everyone was happy? It didn't make sense. This was the first time Frisk had told him what was happening though, and even if it made him happy that she trusted him, he couldn't help feeling guilty for all the times he'd been forced to kill her while she was under that other humans control. Sure, when they had met again after that first genocide loop she had immediately told him that she forgave him and would rather die at his hands than live with the sins she'd been forced to commit. But even so... every time he watched her soul shatter it had felt as if a piece of himself had died as well.

"Maybe that's where the problem lies..." The monster contemplated aloud, snapping back to their conversation as he pulled away to meet her eyes. "If you lose your determination every time you break the barrier then maybe we should stop trying to reach the surface. You told me before that you have no family to return to so... would it really be so bad to stay down here. You'll have friends who care very deeply for you and you wouldn't be alone like you were aboveground. So, what do ya say buddy?"

"But what about the others?" The small human replied, voice tinged with sadness. "They want to be released from this place and I'm the only one who can help them."

"Listen kiddo..." The jokester stated, upset that so much pressure had been placed on the girls small shoulders. "There's always a next time. Eventually another human will fall down here and we can try to break the barrier then. For now, let's just focus on getting you through this."

The child turned her back to him as he finished speaking, but not before Sans saw the glint of something silver shining in her small hands. His soul clenched in fear as he took a wary step toward the little girl.

"That still wouldn't solve the problem though, would it?" He heard the kid mumble as he took another step. "No... we need to get rid of Chara once and for all and the only way to do that is while I'm the one in control. She won't be able to reset this time..."

Frisk turned back to face the approaching skeleton, the sharpened knife held in front of her defensively. Sans held up both hands in a nonthreatening manner, not wanting his friend to do anything rash.

"Where'd you get that knife kiddo?" He questioned warily, swiftly summoning his magic as he glanced at the bar that appeared above her... noting with relief that she hadn't gained any LV.

"I'm so sorry, Sans... I just want to be free." She revealed, face hidden by a curtain of hair.

"What are you..." He began, only to have the words catch in his throat, watching with panic-stricken eyes as the girl turned the knife on herself.

Before he had the chance to use his powers Frisk had already made her move, the tip of the blade piercing through the middle of her chest, not stopping until it was wedged in to the hilt.

"FRISK!" Sans cried sorrowfully, catching her limp form as she started to fall. "No, no, no, no, no... come on kid! Don't do this to me!"

The pun loving monster sat on the ground, the human child cradled against his chest as he gently rocked her. A strangled breath alerted him to the fact that she was still alive and he bent closer to her face as she tried to speak.

"Please Sans..." The child gasped painfully, struggling to get air into her damaged lungs. "S...since I'm in control Chara... can't reset. She'll try to... escape my body. Y...you've got to destroy her. It's the... only w...way."

"Frisk, you've got to hang on." He pleaded, voice cracking as he tried in vain to stop the bleeding. "Just stay determined."

"There's n...no time!" She cried out, startling the skeleton as she used what little strength she had left. "H...here she co...comes!"

All of a sudden a shriveled black heart shot out of the bloody wound, hovering for a moment as it seemed to laugh before flying off. Sans immediately manifested a pack of gaster blasters, tears streaming down his cheek bones as he sent them after it... he had more important matters to deal with. Using the hem of his hoodie, Sans wiped away the blood leaking from the corner of his child's mouth.

"It's gonna be okay... " A pained sob escaped his throat as the child's red soul became visible and began to shatter. "I'm gonna take care of you buddy... I... I promise!"

Using his magic Sans attempted to hold the small heart together, but no matter what he did the cracks continued to spread. Below his hands, the small ten year old choked out a breathy laugh.

"I... thought you didn't... like making pr...promises." She wheezed, voice barely more than a whisper.

"I usually don't." The short monster admitted before locking his desperate eyes on her dulled chocolate ones. "But I'd do anything for you."

Frisk smiled up at him, lips bloody and skin pale, but still... it was a smile none the less. Sans returned it to the best of his ability though anyone would be able to tell it was forced. Moments later, the kid stopped breathing.

"Frisk?" The skeleton asked, nearly inaudible in the stillness, before throwing his head back and letting loose a heartrending scream. "FRISK! NOOOOO!"

His magic shook, barely able to hold the tattered soul together, but he knew he'd have to work fast. So, determination filling his eyes, Sans directed more of his power into the child... hoping he could heal the damage that had been done. He knew he wasn't very good at healing but this was his last chance to save the girl that was currently being held in his lap. As the wound slowly closed he watched with bated breath to see if it had any effect of the childs current state. Nothing happened. Frisk remained unresponsive to everything around her. With his last hopes crushed, Sans allowed himself to breakdown... yet even so, he still kept his magic wrapped protectively around the tiny, damaged heart.

"I'm sorry, I'm sorry... oh god Frisk, I'm so sorry." The skeleton sobbed, holding the girls motionless body in his arms. "I should h...have found a way to get rid of that brat b...before this happened! I sh...should have been able to protect y...you! This is all my fa...fault. I'm so s...sorry..."

He sat there, wishing it were all just some horrible nightmare as he repeated his apology over and over. His head hung low, eyes clenched tight as he thought of everything he'd been through with the child. Sans now realized that over the course of the timelines he had begun to think of Frisk as his daughter. True, he was only twenty-four, but she had become one of the most important people in his life along with his older brother Papyrus... and now she was gone.

"Why? Why did you... I could have helped!" He shouted, voice reflecting the anguish he felt inside. "Please Frisk... just reset... come on kiddo... COME BACK TO ME!"

The distraught skeletons tears fell heavily, seeping into the crumbling soul of the child he had loved so dearly. Up above, the glowing crystals in the ceiling dimmed, signifying night had fallen upon the underground and still he sat there. His magic was beginning to run dry and Sans knew that he would have to let her go... this isn't what Frisk would have wanted. She would have been horrified to know that he'd spent so much time here, crumpled in broken heap on the snow covered ground as her body slowly lost the warmth it had once possessed. No... she would have wanted him to go home, spend time with Papyrus, live a happy life. The little girl he knew wouldn't have wanted him to languish in his thoughts of what could have been when he had the rest of his life ahead of him. The weary monster laughed bitterly as his magic sputtered slightly before finally giving out, releasing the fragile soul inside. How was it that after all this time, after so many loops, he was still helpless to save the ones he cared for the most? Collapsing on the frozen ground beside the lifeless child, his hand resting softly atop her head, Sans closed his eyes and let the exhaustion claim him.

AN: Thanks for reading and as I said before I promise the next chapter will be a lot happier. I really hope you like it :) Please let me know what you think!