I have not thought I'd get the opportunity, but here it is, let's quote some Freud!
Now Freud did not talk that much about vaginas, because he was a proud man of priorities and principles, but they are in fact also part of the digestive system and one of his main arguments is, that our views on sexuality are a product of cultural instructions (obviously) and that what is considered "normal" holds a lot of elements of perversion and fetishism, so that in the end, that which is commonly considered perverse is just a variation or in rare cases exaggeration of the sexual norm.
I honestly forgot where I wanted to go with this. I rest my case.
EDIT: I derailed didn't I?