Although the subject matter is clearly not musical in nature, I think it would be quite accurate to put it under the heading of Folklore. The words people have used to refer to these body parts has evolved considerably over the centuries as was pointed out in a previous post.

But if you insist on a musical tie, My Mistress' Cunny should inject a "proper" musical note to the thread.

Thank goodness we have the Thread Police to watch over us!