Had Crowley imagined a moment in which Aziraphale was asking him to remove his trousers----and he has, of course, but he'd never admit it aloud no matter how much wine he'd drank---he would never have wanted it to be in such a medicinal and clinical situation. Injured by a bloody demon and he has to have his leg looked at. Great, that.

"All right, all right," he says, fumbling a bit with his belt. "It's probably something basic, he's not one for imagination. Think---flesh-eating, limb-rotting. The sort of turn-you-into-stone nonsense that demons are known for. He doesn't step out of the box, Hastur. And if he did, it wouldn't be tough to break it. Probably just a simple ritual to counteract it."

He hopes. It's all a hope. Hastur is boring, but dangerous. He was a Duke of Hell, after all.

He pulls his trousers off, to reveal a black spot growing beneath the skin on his thigh. Something unpleasant brewing there.