The womanless stone

Though identical to his old stone in appearance, Jon's new stone was the womanless stone. It worked like the old stone except if used to mix or alter gender it cannot make a man into a woman. You can give a man tits or a vagina unless he is androgynous or of effeminate built (feminine built men cannot be made more feminine). Just not both. You also cannot make a woman into another woman with it or make large female bodied changes to women. How ever you can make women into men or mix gender traits with it.