Undertale AU One-shots

28 days to fall in love - Yandere Papyrus x reader

Day Zero*

"Dear diary,
I love my beloved more than anyone else in this world. I know that because no one else had done as much as I have for them. There is one little problem thought. I'm completely unexperienced in the field of dating. You see, I want my beloved to be impressed with how good I am at everything, so they would fall in love with me without needing to actually do anything drastic. To fix that problem, I have decided to fake date one girl, (Similar, but not completely your name) was it? I don't really care if really. She had promised me to teach everything I should know. Why? Well, I may have accidentally discovered a little secret of hers that she doesn't want me to tell the whole university. Well, I hope she will teach me good things so I could impress my beloved, if not, I wouldn't want another body to add up to my body count"

Day one*

"Dear diary,
Her name is (Y/N), close enough to the name I thought it was hers. Today she told me she was going to teach me about conversations to have on our first date so I wouldn't be boring. How bold of her! I'm never boring. I'm Papyrus, of course I have a lot of interesting conversations to talk about with my beloved."

"Dear Diary,
I may have been a little bit wrong on that point. (Y/N) had told that I talk a little bit too much about myself. She also explained why that was a bad thing, especially on a first date. She explained that you need to show your partner that you care about them more than yourself and that you aren't just a self-loving prick. I thought I was going to be hurt because of what she said, but it actually made sense. I had lots of fun today."

Day two*

"Dear diary,
After yesterday, I decided to fully listen to what (Y/N) was going to teach me. She clearly had more experience than me, and seemed to know what she was doing. Today she was going to teach me about respecting values in a relationship and trying to be on the same page with them. I'm a little bit confused on that point. I always thought that in a relationship only one person had a say, and the other had to listen to whatever the other said without any objections. I'm really learning a lot in these few days. I'm excited to see what I will learn after spending more time with her"

Day three*

"Dear diary,
I know it's really early to say this, but I think (Y/N) and I will be great friends! When I will be in an official relationship with my beloved, then she could help me out even more! I'm so happy I'm doing this. Oh, also (Y/N) and I are going to go to the park today. She said she was going to teach me about trusting my beloved. I thought that snooping around their life was a good idea, but (Y/N) told me differently! She told me that if I would ever get caught, (She strictly told me that I eventually would) then my beloved would hate me for sure! Oh, I don't want that, so (Y/n) was going to teach me how to calmly talk about something without scaring the other away, and resolving the problems in a relationship."

Day four*

"Dear Diary,
Today we talked about quite a weird topic. It was about how looks, height, job description, or income bracket won't make someone love you more. I always thought that that's exactly what makes people fall in love with one another. (Y/N) told me the exact opposite. After our conversation, I came out knowing a lot more now. I think I'm really changing for the better here. When I will be in a relationship with my beloved, I will really need to thank (Y/N) for all the things she is doing and teaching me."

Day five*

"Dear Diary,
It seems that by the day our conversations are getting weirder and weirder. She told me that comparing relationships with other ones isn't a good thing. I never had thought of doing that, so why didn't I stop her from talking? I really don't know myself. I had noticed that her voice is very nice. When we first met she was very cold, but now she's a lot more gentle when talking! I like it very much, my beloved never talks like this with me"