
Long ago, there reigned a mighty king named Ila. Once while hunting, he came upon a grove where Shiva was making love with Parvati, and surprise of surprises, Shiva had taken the form of a woman to please her. Everything in the woods, even the trees had become female, and as he approached even King Ila himself was transformed into a woman! Shiva laughed out aloud and told him to ask for any boon except that of masculinity.
Thus says the Shaktisangama Tantra:
