¡°But ¡ª I stopped Sirius and Professor Lupin from killing Pettigrew! That makes it my fault if Voldemort comes back!¡±
¡°But you just said it! You said the Dark Lord ¡ª¡±
Hermione listened to what had just happened with her mouth open yet again.
¡°This is a useful little spell,¡± he told the class over his shoulder. ¡°Please watch closely.¡±
¡°But then Dumbledore became Headmaster, and he was sympathetic. He said that as long as we took certain precautions, there was no reason I shouldn't come to school¡.¡± Lupin sighed, and looked directly at Harry. ¡°I told you, months ago, that the Whomping Willow was planted the year I came to Hogwarts. The truth is that it was planted because I came to Hogwarts. This house¡± ¡ª Lupin looked miserably around the room, ¡ª ¡°the tunnel that leads to it ¡ª they were built for my use. Once a month, I was smuggled out of the castle, into this place, to transform. The tree was placed at the tunnel mouth to stop anyone coming across me while I was dangerous.¡±