{requests OPEN!} Undertale Au Characters x reader One-shots

Sans x Irresolution!Ex-genocide!reader

A/N: Irresolution = Anti-Determination. I cant find any information on the Anti-souls so headcannon: you were Frisk's twin, and everyone assumed you had determination, despite it truly being irresolution. you convinced Frisk (under Chara's influence) to do a genocide together. this story is what happened a few resets later...

The surface. its all the monsters wanted to see. you set them free a long time ago with your twin's help. through determination, you made it. you could see the sun again. however...a child in your dreams told you that you weren't determination, but IRRESOLUTION. they said that, if you could kill every monster in the underground with frisk's help, they would make you into determination, like your twin sister, Frisk.

You had agreed.

you had betrayed your friends.

you convinced frisk to end the monsters.

you had made it to the end, and met the child from your dreams. they congratulated you on making it this far. they called you and Frisk 'partners'. then they killed you. you were forced to start again, sorry for yourself. but regretted not finishing the demon off.

That happened a looooooooong time ago. you were there again, and had been for a long time. but your incompletion of the old route, the irresolution in the past, it annoyed you, leading you into depression. your current life consisted of sitting on the couch and crying, or staying in your room and sleeping.

everyone, especially Papyrus and Frisk, tried to help you. you only shut them out, pushing them away. you stayed in your room. no-one came in, and you never came out. for two full days. finally, someone came in to check on you.

that someone...was Sans. your crush a few timelines ago. and you still liked him now. but that's another thing that caused your depression to become stronger. he wouldn't like you back, you killed everyone! he wouldn't care...

"Hey kid, come out. Tori's worried b'out you," he says. you roll over and let your tears stream down your face. Sans put a hand on your shoulder, and you flinched violently. he retracted his hand, scared for you. he tried to roll you onto your back, and you sighed in defeat, letting him move you. you didn't meet his eyes though, brushing hair in your eyes.

"G...g-go...a...awa...y..." you mutter.

"Y/N, no. Tori and the others want-"

"Want...m..e...d-de..ad..." you reply.

"what? kiddo no...just...come out of your room and eat," he says before leaving. you half wish he stayed.

a day had passed. you only went out once to grab some workout tape and a knife. no-one saw you as your headed to the basement. it was multi-functional, with all soughts of tech and stuff. you headed to the workout section, wrapping your hands up.

you pulled of your (f/c) jumper off, revealing your scars and cuts littered everywhere on your arms and chest. you tried not to look at the cuts. you began hitting the punching bag, causing the cuts to open, bleeding onto the carpet. you weren't going to bother to clean it up.

~Sans p.o.v~

The kid hasn't left there room for ages. I tried to talk to them, but they still haven't left, but something was telling me otherwise. its the dead of night, and I feel like Y/N is trying to do something.

I get up, my excuse if anyone sees me being that I wanted ketchup. which was true. I enter the kitchen and grab the ketchup from the fridge, turn around and see a figure holding a knife, heading down the stairs.