Percy continued not to notice what they were up to, as the days passed. They made a point of intermittently really doing their homework, so that it wouldn't seem bizarre that they were spending so much time in the library recently. McGonagall actually looked vaguely approving when they came to talk to her, saying, "I am very pleased that you have been doing your work more consistently as of late," which was quite nice, for all that it vanished at once as soon as they asked her their question. Then at once the usual stern look was back, and along with it their Head of House's disapproval in full force. "Professor Snape is a respected member of our faculty, as is Professor Quirrell," she said sharply, "and I will not hear such baseless accusations from my students. At any rate, the third-floor corridor is perfectly well-protected, and for that matter none of your business!"