His Borrowed Body.

When Kimberly Coxswain drunkenly confesses her desire to be a man "you know, to experience having a dick" to her housemate he agrees to let her borrow his body as a joke and Kim falls asleep. She wakes up to discover that her dream has come true and she indulges her wildest desires in his borrowed body.

Warning: contains material inappropriate for minors including hot blowjobs, masturbation, steamy shower sex, and an ending that leaves everyone's expectations upside down! 5,600 words.