Reiji you coward. You intentionally told Sensei so that she will kill Mao for you. Then Sensei will get caught and you fuck Nagi all day. That's the ending you want.
Oh, man. This cycle. I've seen a similar situation. My relative was abandoned by his father when he was little. But when he became a father himself, he left his own children as well. I find it hard to understand. He became someone he hates.