When a
man and a woman are having sex in a bed and the
man lays on his back, his penis erect, and the woman jumps into the air off the mattress and tries to aim her self in such a way that her vagina lands over the
man'
s penis (his penis entering her vagina) leaving him unharmed. It is like the game of horse shoes because you have to try to land an object (the vagina) around a pole (the penis).