Witches on the wall

For those who don't know me well, I'm a huge fan of webcomics.  I have a huge list of comics I follow, and many others that have finished or sadly no longer update.  One of those comics is a wickedly raunchy episodic offering often set in some sort of Medieval fantasy world (very NSFW).  I just noticed the title of this particular posting and had some vague deja vu, so I googled the word.  Sheela na gig, as it turns out, is quite an interesting subject.  They're these little ugly carvings of women with exaggerated naughty parts... and they're found on churches in Ireland!  They provide protection from evil much in the same way that gargoyles do.  As for their origin, one theory is that they represent the ugliness of female lust.  I think this sounds like a hastily concocted explanation by some embarrassed church official, which is why I like the other theory so much better.  It's thought that they might be leftover goddess figures from before Christianity took over.  The idea that they were created for some purpose independent of the church makes sense to me since a lot of them are made of different material than the building they've been attached to.  Although there's a ridiculous amount of these figures in Ireland, they can actually be found all over Europe in lesser quantities.