undertale sans x reader

why do you hate me after all I've done is spare?

I look down at the floor, trying not to think about my past mistakes, but it was hard to when a freaky powerful skeleton is staring at you hatefully. I don't get it, why does he still hate me after sparing anyone and trying to avoid fights? I guess it's gonna take more than that to have him forgive me. I began to grow increasingly tired, but I didn't want to sleep, so I stayed up with thoughts in my head on how can I erase genocide from all of those who remember timelines?  As I kept thinking, sans snapped his fingers in front of my face to get my attention. "Huh? Oh, sorry sans, I spaced out, w-what is it?" I asked in a still quiet and small voice.

~sans pov~ (yay!! It's sansy!!!)

I noticed the older human was just staring at the floor, so I walked over and snapped my fingers in front of her face to get her attention. "Huh? Oh, sorry sans, I spaced out, w-what is it?" I heard her ask in the quietest and smallest voice I've ever heard. I sighed, I knew I shouldn't really let her stay, last time she ended up turning into chara. But none the less, it looks like she's a pacifist for now. "Get up, you're sleeping in my room so I can keep an eye socket on you. You sister is sleeping in paps's room since she really isn't a problem." She looked nervous at that note, what is it that has her so on edge? Is it because the way I've been treating her? Or is there something she's not telling me? I shake it off for now, and lead her to my room. Once we reach my room, she asks if we have any extra blankets. I nodded and opened my closet to pull out a comforter that looked like a galaxy. I set the comforter on my bed, taking my sheets off, then I make the bed and turn back to her. "You'll take the bed, I don't really sleep at night since, uk, I'm a skeleton. And plus I sleep all day. And I wanted to ask a few questions about why you are the way you are." I said in a monotoned voice. She nodded, not looking at me but looking at the floor again. What is with this girl? (Or boy, or nonbionary, it doesn't matter to me.)

Reader's pov

I gulped, I knew he was eventually going to get curious of my behavior, the truth is, Amelia started the last genocide run, I just finished it because she couldn't get past sans. I didn't want him mad at my sister because well, she didn't want to do genocide, she was threatened at school that if she didn't do genocide, they would cut her down to the size of her personality, which she doesn't show often. "Here's the first question, why did you do genocide run last timeline?" Crap!! I knew he was gonna ask that one first. I took a deep breath and decided to tell the truth about how my sister was threatened to start it and finish it. "I-i didn't really start it, Amelia did, but she didn't want to." I started to explain but he cut me off. "Wait wait wait!! So your sister that is scared of pretty much everything started genocide!?! That's hard to believe coming from you." He said with a glare. "I know it's hard to believe, but if she didn't, she would probably be dead right now and I'd be on a war path back at home. She was threatened to start it, but she couldn't finish you off, and if she didn't finish genocide, she still would've been dead. So she asked me to finish it for her so the people bullying her would leave her alone. At first I didn't want to did it, but in the end I had no choice because she wasn't  that skilled with things like that, she's too timid for her own good. So I finished genocide for her, but I felt too guilty to actually erase it, so I reset, and that's how I ended up here, Amelia came home and passed by my laptop, she went over to it and got sucked in as well. That's why." I explained while not looking or making any eye contact with sans as possible. He seemed to calm down down, like he was starting to understand why we did it, burst the same time, having more questions pop up in his skull. "OK, that actually is pretty understandable,but why didn't she just tell you about the bullying?" I thought about it, and couldn't really come up with any answer except. "I think she wanted to be brave, to show that she wasn't that scared of everything. But in the end it just caused her a lot of trouble." I said carefully. he nodded, seeming to know that feeling quite well. "Now, tell me, is the way you're acting right now because of how I'm treating you?" He asked. I titled my head, not completely sure what he meant. "Why are you acting timid of me? That's what I mean. Is it because I've been treating you to harshly?" He asked while making it more clear. I gulped nervously, this question, startled me. But none the less, I answered. "I just want to know why you hate me after all I've done is spare in this run. But I was Africa's to ask so I kept quiet." He looked shocked for a minute. He stared at me for a good while but I became self-conscious and hung my head and looked away. "I don't hate you, I was just being careful to not make the same mistake twice by trusting you too quickly. I didn't mean to make it seem that I hate you. In fact, I kinda like you." He said slowly and gently. I blushed, so he was just being cautious about his and my actions. That's understandable for the both of us. "I like you too sans." I said quietly, button the point where he could hear me. He smiled and told to get some rest while laying down himself. I'm glad he doesn't hate me.