I always wondered if the Ozzie/Zild term "sheila" as a generic term for a woman or a girl owes it roots to "Sheila Na Gig" there are several sites about Sheila-- an irish god similar to Kali-- sometime portrayed as old woman, some time with a skull-- not a head-- some times grinning-- (or is it with teeth bared?) and alway with her legs spread and her vulva open.. some images ( many have been destroyed)--i thought this was one of the best.. since it has several images.. (and most are scarier that erotic!) She was a god of Birth/regeneration and of death.. a death head , a sexual inviting vulva...
http://www.rci.rutgers.edu/~jup/witches/qa/q126.html