Betting this isn't really anything. I bet Shuuji killed himself due to depression. Signs are all there, no sense of satisfaction in life. It happens if everything is seemingly handed to you and you don't set and achieve your own goals, or find those goals too easy to accomplish.
I've been in that situation before. You know they're just using you but you don't care because it means they're close to you. It's seriously painful and the longer you're in it the more it hurts. Rip the band-aid off my man.
This seems like obvious hyperbole red herring. Plenty of times I wanted to 'kill my friend' when we roughhoused as friends. Didn't mean it literally. Don't think MC is capable of hurting a fly (purposefully) unless he maybe just completely snapped after seeing him hit FMC or something.
Aight fuck the goth chick outta the gate. But yeah, seems like Haruma definitely dealing with some trauma and memory loss. Question is how involved was he with Shuuji's death?
Fuck you might be right about B. "You should be happy he's moving forward now" is a huuuge pointer to that.
Shit maybe he even helped kill him? If he was beating on her, saw it and snapped or something?