@Ryouko_Endou he's probably the one who broke the phone. I guess he doesn't like the bullies, like ever, but he doen't willing to help his bully's daughter so easily. He is basically a passive character, if the heroine asks for his help, he might help her.
@Ryouko_Endou Considering the previous chapters,if the student ask for his help he'll act otherwise he'll let things escalated to the max and them destroy the bullies lives with a video
I can already see how that teacher is going to turn on the girl once she finds out that his father was just playing with here. It is true that she doesn't really care that much for here and is just using here to fuel here delusion that she is going to be the new partner of his father. I just wonder what will come first she realizing that his father is cheating or his father dumping the teacher. I'm guessing she will found out about the cheating first.