Responses
Personally I felt he was very overdramatic there. The scene wasn't completely shown there so we don't know if Nojima confronted Hikaru afterwards or not. Also I question how strong their "friendship" was. Before Nojima's girlfriend confessed to him they weren't friends, not from Hikaru's perspective anyways. I can see why he closed off his heart part due to some unbearable guilt but not why he felt it was appropriate to rape Haruki. I have some guesses about what's going on but honestly I think that whole scene could have been explained a bit better with a little more detail.
I just realized that all this was triggered because Hikaru was blamed for something that he did not do. Remember when Nojima's girlfriend was trying to ask Hikaru out, kissed him against his wishes, and Nojima saw? And right after, Hikaru went and raped Haruki?
Not to absolve Hikaru of his crimes, but shit happens. Maybe Nojima and Hikaru should have kust talked it out, and all this wouldn't have happened.....