Friday is when Peter finished reading the diary.  There was so much Death and details, which made it hard to read.  He now understood.

(Y/n)'s father killed his parents.

They found his body at the scene. He never was a suspect.  But here are facts that where never put into the public.... and how would a now dead man know and be able to write these.

"Oh my goodness..." he mutters looking at the sleeping girl on his lap.  She's been having bad dreams and her stomach swelling faster.  She probably won't be able to stay the rest of the year without bullies.

Peter looks at her and tries to figure out if this fact truly does effect them.  Yeah it's not a good thing that happened... but she isn't her parents and he isn't his.  She is sweet and has a desire to actually help people when she isn't full of the murder, which may not be a permanent thing.

Peter decides that he actually does love her.  He fell for who she is.  The sweet and shy part of her, but also the confident and flirty part.  He loves how she always pushes her hair back when she is flustered. He loves how her face lights up when she talks about her love of the arts. He loves how she has absolutely opened herself up as much as a person who has been through so much can.

He absolutely loves her completely. And the fact that her parents were killers and his were killed by hers... doesn't change that fact. It's the past and his love for her is in the present.