Remus Lupin

You are dating Remus and you have been dating for 3 months. And once every month he goes to bed early (Or at least he calms he is), and the next 3 days after that he doesn't talk to you,. You only see him in class, and he sits with his friends (James, Sirius, and Peter), and as far away from you as he can. But ather those 3 days he goes back to hanging out with you, and he acts like nothing happened. You're starting to wonder what he's hiding from you. It's your 5th year at Hogwarts. Chrams class just ended, and you're heading to the library with Remus, and he's acting like he didn't just spend 3 days without you.