"Professor Sinistra adapted to the second system quite expertly," Draco says, with a tinge of envy and admiration. Now that he has the chance to think about it, outside of Astronomy classes and events at the Great Hall she was rarely ever seen moving away from the comfort of her own office, that even the tower scarcely showed her presence. "I suppose that's what prefects and Head students are for."

And teachers, of course, as they will probably need to patrol once in a while, just as their professors did when they were in school.