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Speaking for my wife . . .
My wife likes fingering me anally not because it turns her on, but because she knows it turns me on and she likes to pleasure me just as I like to pleasure her.
What technique? Generally, with me lying on my back, she starts with her index finger on her right hand and massages my prostate. Then she adds her middle finger and then her ring finger. Then she slowly and gently inserts her entire hand and then turns and twists her hand. Meanwhile, her left hand plays with my penis and testicles and occasionally, she does a little oral. Sometimes, I will turn on my side and sometimes onto all fours. We have a replica of a woman's hand with fingers pointed together, not a fist, for when my wife's hand and wrist get tired.
Precautions? I do a quick clean out beforehand with my enema-connected-to-the-toilet system.
Finish to orgasm? Generally, yes.
Rectal stimulation only? No. I need to add stimulation to my penis. Incidentally, my wife can do it and it feels good, but she can't do it rigorously enough, and for me at 67, it needs to be pretty rigorous, so I help.
Additional info: After playing around as described above, my wife inserts multiple anal toys and dildos, general one at a time. This can lead to pegging.
Specific circumstances for anal fingering and anal play over intercourse? The above takes place once a week, and occasionally, twice. We try to have vaginal intercourse every day, but not with the goal of orgasm. If orgasm happens, it happens, but it generally takes too much energy and effort to reach orgasm more than once or twice a week. Every day, we just try to roll around in the hay for 15 to 30 minutes with my winky in her hoo-haw.
For the fact checker looking for inconsistencies across my various experiences, we don't actually "roll around in the hay." Please don't take the statement as an embellishment or a misrepresentation of the truth. That is simply a euphemism for having sex in our bed. We don't have any hay on the property and I'm sure we would both find hay to be way too scratchy.
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