"Mr. Longbottom didn't come with you?" he asked, glancing down at the map and not seeing Neville's footprints anywhere near the classroom. He was surprised, really, and it may have showed for just a moment. It was obvious to anyone who knew them how protective Neville was of Susan. And given the way he insisted on being with her for animagus training, Sirius was shocked he hadn't accompanied her to detention. Then again, he was still mulling over the fact that Neville hadn't been with Ginny and Susan when he'd caught them out of bounds.
He crossed his arms and looked at her. "What do you think your lines should be tonight, Susan?"