Parvati's expression darkened. Why did she need to show her hands? She didn't understand...
Oh.
"Something has happened to a student," she concluded. "And you think I've done it." Parvati hadn't done anything, yet she had had thoughts. She had to get the staff and students to take the murder of her friend seriously, and she knew more destruction would make them see. And now it had happened, and Parvati found herself glad that it had. And she knew that showed on her face.