So when he heard the door of the room Hermione shared with Ginny open late at night, Harry followed her down the stairs without hesitation. All three of them were staying at the Burrow for the summer. The Dursleys had given permission. Harry didn’t know why, but he had the feeling it had to do with the word Hermione had whispered at Uncle Vernon at the train station, the end of their first year. Something that sound like, "Imperio."