In Greek Mythology, the Empusae are considered to be 'filthy ass-haunched demons' (often also described as wearing 'brazen slippers'). Their main habit seemed to be that of frightening travellers, but they could be scared off by insults, at which they run off screaming. They were said to disguise themselves as dogs, cows, or beautiful women, who suck the life from any man foolish enough to end up in bed with her. To my mind they sound equivalent to vampires in modern folklore, but a bit more wussy.