Sometimes when I come extremely close to ejaculation and feel a small discharge of seminal fluid coming up, I loosen my sphincter and body muscles suddenly to stop ejaculation.
Then a totally different flavor of a new orgasm comes. The source of this orgasm is the prostate-perineum-anal area. I noticed that when I come, my anus contracts and tightens up, this pushes my orgasms beyond the normal limit. JJ