By the time they reach the top of the stairs, his wings have disappeared again. There's still blood on his shirt, but he isn't even holding the arm stiffly, so presumably it's either healed up or he isn't affected by pain. He gestures, and the music turns off.

"I don't know why you're looking like that," he says, sitting in the same chair he'd occupied before. "Seems you knew what Crowley was, to some extent. You couldn't have expected that no one would come looking."

Given Crowley's public persona, that is actually a perfectly reasonable assumption. But Lizzie, he reasons, would know that Crowley's public persona was a bit of a jump from the reality of his existence. He'd had a long time to form acquaintances.