@CronosusCZ I noted last chapter (but kind of late) that this can blow up in the evil girls' faces
really badly. Haruto's two friends are two of the most popular guys in school, and one of them was there for the confession and saw that the other girl was pushing it along. If those two guys simply told all their friends and classmates about how evil those girls were for forcing Asahina into trying to hurt their friend Haruto, it would absolute destroy their social lives. As in, everyone in the school hates them, no one talks to them, people keep destroying their books and messing with their shoes in their shoe locker, and so on. They definitely didn't think this through.
@Starbright Asahina is far too insecure and timid to even tell her family about the abuse. It seems stupid, but that's actually a fairly common response to abuse. (Witness how many people stay with abusive boyfriends/girlfriends/spouses, even when there's physical abuse happening.) For whatever reason she's incapable of standing up for herself enough to even ask her parents to transfer her to a new school.