I’m doing some research for what might become a future novel, and came across this passage in At The Bottom of the Garden, by Diane Purkiss, which absolutely cracked me up:

Another incomplete Greek demon is Empousa, who shifts shape like Erinna’s Mormo. When Empousa appears to Xanthias and Dionysos in Aristophanes play Frogs, she has a phosphorescent face, and transforms herself from a bull to a mule to a beautiful young girl, then to a dog. She makes her appearance in the underworld, the land of the dead, linking her with the other demons of death. She also resembles the other demons in that she uses seductive powers to attract men; when she manifests herself as a beautiful young girl, Dionysos cries, ‘Let me get to her!’ He is only deterred when she turns hurriedly into a dog. They notice that she has one brass leg, and the other is made of shit. Unsurprisingly, their enthusiasm for intercourse with her ebbs sharply.