He let out a bored sigh and started explaining, lies shamelessly leaving his mouth. "Since the library was about to close and they refused to leave, not to mention they were at the Restricted section, I decided to play a little prank on them." He grinned, that sent chills down Hermione's spine, but she didn't give it away. "It went so well, the idiot pissed himself and the girl puked all over the floor. Simple."