"Everything is fine, Neville," he said. And then he added, pointedly, "but everything would not be fine if you had left the Tower to try to warn me, because McGonagall would have caught you instead of just catching Malfoy, and then the both of you would be in trouble." He smiled a little at the understanding that bloomed across Neville's nervous face then. "See? That is why I told you all to stay put," he explained. "Sometimes problems are much better solved with sense than with Gryffindoring." And off Neville went up the stairs, and Percy headed to his own bed, yawning, and feeling as if he'd actually managed to teach a valuable lesson.