Michael and Lucifer had established a routine ever since their father de-powered them and threw them in a house together.
During the day, they fought. Sometimes they used words and sometimes they used fists. Now, they could break each other more easily. This danger added a thrill to the game.
At night, Lucifer would join Michael in his bed. Michael never took the initiative to go to Lucifer first.
Michael feared that one night Lucifer would decide that he didn't want to sleep by his side anymore. Then, Michael would have to admit to Lucifer and himself that he needed Lucifer there. But he didn't need to worry because Lucifer already knew how Michael felt.