Hermione acquiesced immediately, knowing that this was one thing that she shouldn't resist them on. The others followed mutely behind them as they went up the stairs to the boys" dormitory. Once they were all inside, Sirius whirled around and grabbed Hermione by the shoulders. James was clearly leaving the interrogation to him, whether because Sirius was the more expressive of the two or because James just couldn't stand to look at her at that moment. "What do you know and how do you know it?" Sirius demanded, his voice so stentorian that normally Hermione would have been uncomfortable.