I was always curious (and maybe a bit bothered) why the "Penis" tag is, well, the proper word for that piece of anatomy while the Vagina tag is relegated to slang word for it, "Pussy". I think these two should match, either slang word for slang word (Cock and Pussy) or proper word for proper word (Vagina and Penis).
Especially since we already have other well-stocked tags with the words Vagina in them.
Updated