I am a male heterosexual. I say that only because so many readers seem to confuse a writer's gender and orientation. I have a fantasy in which I am tied naked to a block of some sort in an open field, with my consent, which leaves my bottom exposed. A long line of men, maybe 20-25, sodomize me. Some go around more than once. When they are finished, I get dressed and go home. In real life, I never experienced this type of sex.