Ugh this Manga's sensibilities are off. I hope it's not "Japan". Please no harassing and bullying and discriminating against a clear VICTIM whose been suffering since childhood, and please stop acting like it's not gross AF for a university aged 20 year to potentially get in a relationship with a 15 year old. If it happens... fine (I think he needs someone more like family though), but like it's so weird that the supermarket Co worker last time kept hyping the clear high schooler up as a potential girlfriend. He even talked about how people his age wouldn't be better. And somehow the other staff heard him and didn't chastise him for that?? What the hell.
This does just really suck though because there's no just nothing wrong the MC has ever done, but they're also the victim whose parents orphaned them as a child. They already had to deal with losing both parents in a horrific incident and then in addition to that all the bullying and harassment in person and online and then discrimination in the workplace and just finding somewhere to live. I refuse to believe people would be this monsterous. Maybe online and maybe behind his back, but seriously? You expect me to believe these people learn a literal kid was orphaned by his mom killing his dad over an affair and they jump to "Devil child" not "Oh this poor child." in my experience people are at least fake nice about this stuff. Really it's a different kind of awful, but not unreasonably monsterous. Like these people are acting psychotic or like sociopaths with their complete lack of empathy. Are they murderers?
Anyway, this instantly brought to mind a recent SNL skit
Maybe he should just open every greeting with "Hi I'm Greg and my Mom killed my dad naked on TV."