My brother just finished reading good omens and he brings up a possibility: Crowley visits Aziraphale in the bookshop one day only to have his ankle broken upon opening the door in some crazy home alone style trap because Zira "thought it would discourage customers." He didn't take into account that the only person who regularly enters the shop is Crowley. Crowley isn't sure if he should be mad about the ankle or thrilled that Zira takes cues from Kevin McAllister, who is clearly a demon