Sans vanished from the clearing not wanting to get dropped by his other self, he appeared by his house, he went to walk in but froze as he looked at the shed a rather obvious piece of paper clung to the door, so he checked it out, it read:
Hey short, red and angry!
Just thought to tell ya, I'll be taking my kid back, but hey it's not a major loss for you huh? Besides I brought you a gift! Hopefully you don't be to awful, they don't deserve that, now, you'll forget all about this when you wake up next and the timeline will fix itself, TIBIA honest I kinda hope you and your paps get along better, my cool bro is really worried about all that, but anyway, the 'gift' won't be erased atleast I don't think, their kinda not supposed to be in any of our timelines, so just leave yourself a note or something inconspicuous like that, just to remind yourself, it is your pet.
From you hehe
Sans stared at the note confused, shrugging he entered and saw you, who jumped in surprise and fear, "well, well guess this is my lucky day" sniggered sans, "hey kid, don't look so worried the good stuffs tomorrow!" chuckled sans darkly, you looked behind him but decided you wouldn't make it out the door and slumped down, and sans left tossing the note into the snow, he put a piece of paper on the door and shut the door, looking at the cave roof as the dusty air began filling the clear spaces, "just as it's supposed to be" nodded sans his mood improving, and he went into his room after sluggishly dragging his body upstairs and collapsed on his bed.
When sans woke up, it was to a rather annoyed shout from his brother, "sans get down here immediately!" shouted papyrus, sans sluggishly got up, "uhhh isn't it to early even for you" complained sans, but he stumbled downstairs, staring at his brother who stood in the opened doorway, "come out here sans!" commanded papyrus, "uhh right boss" sighed sans, he followed papyrus to the shed, "um it's a piece of paper?" pointed out sans as his brother pointed at it, "argh! Read it you imbecile!" shouted papyrus, "ok, ok…." Sans read the paper,
SANS'S PET! NO STINKING BOSSES TOUCH IT!
Shouted the note, sans didn't remember but he had written that note for when frisk was his pet, "huh… ok than… what is this pet exactly?" asked sans freaking out in confusion, "you look, I can't be bothered telling you!" snapped papyrus, "yea, yea fine" yawned sans, glancing at his bro, he stiffened a little bit, not sure where his confidence is coming from, but being confident with his brother is a very dangerous thing, especially if there are other people around, so with a sigh, sans opened the door and gaped at you, huddled on the floor, you jumped to your feet and attacked him, he easily stopped you, "yea seems like my type of pet" agreed sans to himself, his eyes gleaming, you stopped and immediately regretted your actions, "what's that look for? Scared of lil old sansy" chuckled sans darkly, you gulped and tried to struggle away from him, papyrus sighed, "we can deal with it later sans! We have jobs to do" snarled papyrus, he was entertained by the sight but knew he had to do his job, despite the fact they had technically just found a human, papyrus didn't want to give you up, if you could prove to remain entertaining.
Papyrus and sans got ready quickly even for them, both wanted to hurry up and get home to see just how entertaining you are, but they didn't they went to their posts and sans was surprised to see a human child walking down the path with a flower clinging onto them, and sans tricked them into shaking his hand, and they died.
Reloading
Sans offered his hand but the child refused and soon enough papyrus and sans were distracted by the second human they found that day, each time the child day you forget a little bit of your past life.
Did you have a pet?
Did you have a friend?
What was their name?
Where did you live?
Finally sans remembered you and looked down the snowy area as he opened the shed door, "hey brat, have fun? Looking a bit bonely" said sans, you were confused but laughed, you were hungry but didn't want to annoy him, he walked off, "ya comin?" he called, you stared in surprise before agreeing, you followed him distressed over your inability to remember things, if he noticed, he didn't show it, you walked with sans through waterfall and soon enough you both stood in judgment hall, "you better watch this brat, I'll show you, what happens to kind monsters out here" stated sans as a child walked into the room, you couldn't move and watched as sans began to attack the child, they died
Reloading
They won sans's heart somehow, "huh what's up heh? My lil pet didn't even attack me while I was distracted… why… why are you so nice…" he asked his last question directed at the kid, they just shook their head and smiled. "because we're friends" said the kid, who walked past you and your 'owner' who looked like he was crying but he wasn't facing you.
When the barrier shattered it was a nice feeling to be on the surface, sans couldn't get rid of you, mainly because you had nowhere to go but also because he respected you, you could have finished him off,
But you didn't.