Crowley immediately scrambles backwards, dragging his leg with him. As much as he wants to be there for Aziraphale, if Aziraphale did Fall, the angel is terrifying right now. He's falling apart, maggots are falling out of him. He looks like a shambling, walking corpse, still talking to him with that soft, kind voice.

"You're dead, Aziraphale, you're dead!" he shouts. "And now you're----you're----" He stops in his sobbing to make a confused face. "What the fuck is happening to you?"

At this point, the burning second floor falls down near him. Crowley cries out and leaps forward to pull Aziraphale out of the way. Dead or not, he's not going to have his best friend crushed by burning wood.