Group Sex Stories

This a story about two first cousins who have a torrid affair through the years in which many fantasies come true.

What if you had a nifty gadget that could change your sex or the sex of anyone you pointed it at? Think of the fun you could have, turning yourself into a woman for an hour or two, or for years. Think of the mischief you could do, turning men into women, and vice-versa.
Bored with your lover? Turn her into a man and yourself into a woman, then try again. Looking for revenge? Turn that scumbag you despise into a woman for the rest of his life.