Well, there’s a few caveats to this. First, that I’m not sexually attracted to men, which skews perceptions some. Second, that because of that, my experience with men in this way was exclusively via bdsm play where I was topping them (which allowed me to get around the lack of attraction and get erect (though I sometimes had to use support devices like a cock ring to stay erect).

Thirdly, that in terms of numbers of partners, I can count how many men I penetrated with my penis, and those I truly fucked; whereas I lost track of how many women I did anal with. So the comparison is limited.

There are differences. The obvious one is that men are taller and physically larger on average. So positions make the penis go in at different angles sometimes. Since most of the men I fucked were there to be dominated and used, they were bent over for at least part of the act, and you notice the height difference, as well as the more muscled buttocks, when they apply. But even a fairly well muscled and tall woman still has a different hip ratio, so it still isn’t exactly the same.

Someone else mentioned that men sometimes have a hairier backside, and that is the case for some. You can feel the extra hair when it’s present. It’s scratchy as you’re going in, even with a lot of lube. The hair is also much coarser on average, so even very hairy women, the hair isn’t as noticeable during action.

I’d also say that men tend to be a bit more capacious. Not necessarily looser, but once they get relaxed and warmed up, they seem to be able to take more girth, and depth, than women before things get uncomfortable.

A bigger difference shows up when the man is into being fucked, whether or not they’re otherwise bisexual or homosexual in the rest of their life. The men that enjoyed being fucked just responded with more gusto, particularly once things got going and the position was right to hit the prostate. The ones that were only into anal as a form of domination or humiliation were much less likely to really open up and enjoy it, which means they carried more tension if they weren’t all the way broken down before or during the process.

Even when they were broken down into the right frame of mind, the ones that didn’t enjoy anal per se rarely felt “alive” the way someone that likes it does. But even women that love anal don’t typically respond physically the way men sometimes do. The pulsing of their orgasms feels different for one thing, but just the way men vs women feel inside when they’re being fucked in just the right way for them as individuals is different. There’s an extra bit of something that I find difficult to put into words. Best I can say is that the internal motions feel different as the sex happens.

I definitely prefer anal with women because I prefer women, but I suspect that if I were bi, I might prefer anal with men. The sensation of it, if you ignore everything else, is distinct, in my opinion, in a way that stimulated my penis more intensely.

There was a degree of extra fun in breaking a man down with anal though. The men that were gay or bi didn’t often respond to the “threat” of it in as visceral a way. A hetero or very hetero leaning bi man would struggle with themselves more, so I could ride that tension and make the process of making them come by being fucked “worse”, and in the handful of times it happened, their orgasms were intense enough to feel very good to me. Women, for whatever reason it may be, didn’t tend to respond to anal as a tool of dominance and control as viscerally. So, of the ones that orgasmed, it didn’t have that same power to it.

So it’s one of those things where I wouldn’t seek it out. If I were single and horny I’d go home alone rather than try to find a man to fuck. But, in the context of the scene, I didn’t object to topping men when it worked out that way, and if if that meant fucking a man, it did feel good enough that I would occasionally come as well. Not every time, and there were a few times where I couldn’t stay hard even though it felt good physically. I bring that up because of the caveats.

A lot of what people tend to feel during sex is filtered through the brain, and the brain is our biggest erogenous zone. If I were bisexual, I believe that my lived experience of fucking the exact same men in the exact same ways would have been different. And, thus, my perception of the physical stimulation likely would have been different as well. If nothing else, I’m confident that I would have had more orgasms myself, and that I wouldn’t have needed support via cock rings, which tend to slightly alter sensation in their own way (not necessarily better or worse, just slightly different).

I can recommend trying to fuck someone outside of your orientation, btw. I had my kink to bridge over the lack of attraction, so it was easier in that regard. But if someone is somewhere on the gay-bi-straight slider, you can learn a lot about yourself just by making the attempt to cross over your usual attractions. You’d have to find someone willing to help you experiment, but that isn’t a total barrier to entry, so to speak.