@Zinon You're thinking of Hermaphroditus, the son of Aphrodite and Hermes. A (female) nymph fell in love with him and prayed to the gods that they be joined together in marriage. The gods, being assholes, fused them mentally and physically into a single person. But s/he was a really nice and really hot person who watched over mortal marriages forever after! Along with his/her homie Hymen. Good ol' Hymen.
@Tartiris Actually, "Goddess" is totally race-based in most religions. You can have all the same powers, you can do the same cosmic jobs, but if you weren't born or married into the right bloodline, you're just a Demon/Titan/Angel / Fairy/Spirit/Giant/Vanir. So unfair.