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

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

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

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

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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

Why?

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

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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.