for what happened in chapter 3 it ended with him saying “I didn’t mean to hurt hiruma ” skipping chapter 4 but stuff could be brought up there too in chap 5 the black hair guy apologizes bc “my words and actions hurt you” even though the blond guy hurt his feelings, he didnt say back like oh im sorry I hurt your feelings too” or anything all he said was that he was lonely bc he got avoided for abt a week. Tbh I don’t see a reason why hiruma had to apologize
In chapter 3 when their classmates saw them, the blonde one (Takanashi) told them they just happen to run into each other and it's a coincidence that they were together. But that's not true because they are friends and even have a mutual understanding by that time. So that hurt black-haired guy (Hiruma). Takanashi knows this because he said "What do I do...I didn't mean to hurt Hiruma–" in the last page of chapter 3.
Hiruma distanced himself after that (he was hurt being denied as a friend in front of their classmates). Takanashi (blonde) never apologized for that.
We learned how he has some sort of trauma, but he should still apologize. Hiruma even said in chapter 5 that his words and actions hurt Takanashi and Takanashi know it's not true, but he still did not apologize to Hiruma.
So basically it feels off that Hiruma feels bad thinking it was his fault and Takanashi haven't apologized for not wanting to be seen together with him by other people in chapters 3 and 4.

the blond one should’ve apologized whatt