Why do men like to have sex with a woman's ass?

Why?

I now have a lover who is a passionate and enthusiastic fan of anal sex, and she has an ass that is…um, extraordinarily accommodating and a great deal of fun. So, for the first time in my life, I have a partner I actively enjoy giving anal sex to.^3

1. Yes, I prefer underscore_notation to camelCase. It’s easier to read. Change my mind.

Why do liberals think same-sex marriage is alright? The Bible makes it very clear that it's not alright to be gay, why can't liberals understand that?

3. Yes, this does mean I’ll do things during sex I don’t necessarily actively enjoy myself. I think one of the hallmarks of a good lover is willingness to do things that get your partner hot even if they don’t necessarily rev your motor.

2. Giving, anyway. I’ve always been a big fan of receiving, which is why almost all my lovers have been quite skilled with a strapon, and I even own a patent on a new type of strapon.

Throughout my life, until just recently, I’ve had girlfriends who enjoy receiving anal sex, and I’ve always been willing to do it, though I’ve never been a huge fan; too much work for something I personally didn’t find particularly interesting.^2

This is a real question: Why do a lot of men/boys hate (yes, hate) women that voice their criteria in choosing a partner? Even when the criteria is sane and responsible. Besides it being, sadly, an effective mating strategy, why does it exist?

The answer to basically any question of the form “why do $people like $sex_thing”^1 is “because it’s fun.”

Because it’s fun. That’s it. It’s enjoyable and feels good. It’s really not rocket science.