Michael is an omega going through his heat cycle. His have always been more painful than for some omegas, but he usually chooses to deal with them alone. He doesn't want to reveal his omega status to you, his alpha roommate, and is very embarrassed, having been oppressed and tormented his whole life by alphas. You, however, have never asked if he's an omega, and he doesn't intend on letting you know. He has experienced a dysfunctional family, primarily by his father.