I use a TENS unit , one patch over my sphincter and one on just the head of my penis. The black wire always goes to rear patch and red on penis. ( Black in back, red on head ) Orgasm takes less than two minutes, rest five then do it again and again. After four times I'm unable to orgasm again and no matter what my wife does I remain flaccid.
Nice! I like to cum like that too. But I insert one electrode together with the plug into the anus, right on the prostate, and the second one on the head. It feels so much better that way. Try it.