*SPOILERS* This is my personal understanding：Because Hoshino believes that "love is abuse", or he lies to himself that MC's abuse of him is out of love (but it is possible that MC told him that). Otherwise, no one loves him. In BE2, Hoshino discovers that MC doesn't care about him. He thought they were friends, but that was betrayal.（ I used a translator so it might be a little weird.）