So... the ass thing is really going to become a full fledged debate?
I vote pussy.
for a man? an ass feels similar to a vagina maybe tighter, for the woman the anus has more nerve endings than a vagina, so if you're having sex purely for pleasure, other than "the correct hole", the baby making function of the vagina is a moot in that context?
It may have more nerve endings or whatever, but POO comes out of it. It's a godamn hole made to expel everything that is nasty, dirty, and useless to our body.
While a pussy is a godamn work of art. It's shape is beautiful, it has lots of more pieces to play with, it reacts way more sexy to everything, and it's a masterpiece of biology inside while the asshole look like... asshole (HAH!).
If the argument is you're a man but want to be fucked, then ok, we have fewer holes available, it's "understandable". But being a girl with such a beautiful organ and prefering to use the ass? Such a fucking waste.
There's the "well can't make babies in the ass" argument, and that one ok, also understandable. But still, damn, it's such a beautiful organ, the entirety of it. It deserves to be loved more than a fucking hole made for garbage to come out of.