With their characteristics? A simple bully mc wont do. They needed to be connected on a deeper level. If I was being abused at home AND bullied at school, I'd kill myself.
The character and story development were amazing but if Makoto (uke) was bullied from the start by Touma (seme), it would be like Stockholm syndrome. Makoto would depend on him for his existence, he'd need him, but he wont love him. Same with Touma. With his fear of being "unwanted", he'll view Makoto's dependency towards him as an authoritative thing. And psychologically, without meaning to, they'll hurt each other over and over again. And neither of them would realize the negative effects of it because they'd both feel as if its normal to be treated that way.
There's probably other ways for them to connect through their traumas other than the mc getting raped by the love interest surely. I just really find that quite a lazy choice to move the plot, particularly because it is romanticised as with most SA stories in yaoi. Sure Touma did apologize but that scene came across as an afterthought to me. I know, I know this is fiction and etc. etc. as many ppl love to point out but cmon a little bit of effort to deviate from the prevalent tropes in yaoi wouldn't hurt, especially when the story as a whole is quite promising.
That the author was given enough chance to continue the story and improve the relationship and personalityof the characters significantly. My only gripe would be the rape. The love interest can simply be a mean bully without raping the mc. Anyway, this is one of the few mangas w/ rape scenes that are quite good because of how the story unfolds.