I was doing anal like 2 or 3 times a week for almost a year. I don’t think there’s been any permanent loosening, since after a month of not doing it, I wasn’t used to it anymore and it was at least as difficult as the first time.

Difficult, but not necessarily painful in a bad way. The key thing is to make sure you're given more time to relax *after* your partner is inside. Even if they’ve stretched you out really well and entered carefully, usually you clench up and need a second to adjust. If your partner is attentive and responds well to verbal directions, it might not even be necessary to worry about controlling the movement yourself. I thought it was romantic that no matter how good it was feeling for him, he would always hold back for my benefit, until I gave the ok to speed up.

If you’re worried about pain, I wouldn’t recommend lying on your back and pulling your knees up. You feel very trapped and it goes very deep and there’s not a whole lot you can do about it. Hands and knees, or lying flat on my belly, always worked best for me. The only problem with that is your partner can’t see your face, so if you want him/her to ease up you’ll have to say something out loud.

Oh and one more bit of buttknowledge: We’d read someplace that you should always use a condom and we did, but once we made the mistake of getting those non-latex ones that kind of remind me of saran wrap. It was all wrinkly, not smooth like the good old Trojans, and rubbed horribly and I was bleeding. So those condoms are not the way to go.