"And thank goodness for small favors." He followed her without hesitation. It was strange to think of how many places there were in the castle that he had never been, even after spending so many years here. It was better than trying to think about whether he ought to be here at all. Her room was something like he had expected - it seemed warm, and better lived-in than his own, although that wasn't saying very much. He gave in to the urge to look around a little more closely, for a moment. He was quite curious as to what exactly she did when she wasn't grading.
"No," he said, shutting the door behind him as the streak of white shot for his ankles. "We wouldn't want him to escape, never to return, would we?" Then who would come scatter white, wiry hair all over his office? He didn't mind quite as much as he let on, now that he'd found a way to strip it away reliably.