Kokubo-sensei runs the whole middle school as head teacher. He's also the interim homeroom teacher for class 3A, Hinata's third-year class—which has a serious problem. The girls in that class are infamous bullies who drove their previous teacher to a breakdown and forced her to quit.
When Kokubo-sensei takes over, he recognizes the bullying as a spreading poison and acts fast. His solution is direct: he breaks up the bully gang by scattering each girl into different homerooms, cutting off the group dynamic at its source.
Before he steps down from the 3A position, though, he has some meaningful one-on-one conversations with the lead bully. These talks get philosophical—the kind where he actually tries to reach her as a person rather than just disciplining her.
Content compiled by AnimeList.moe from publicly available sources.
