One of the five great Bodhisattvas who live in heaven, one who administers mercy and compassion. She, however, is a vulgar, boob-flashing, hermaphroditic, sexy Bodhisattva. This is the person who ordered the Sanzou Ikkou to go to the west. It may seem like she enjoys sending various trials at Sanzou and the others, but ever since 500 years ago she puts her heart and soul into watching over the way Goku and the others live their lives. In Gaiden, she displays enough natural power to knock out Goku after he'd changed into the Seiten Taisei. She might actually be the strongest. She is portrayed as a hermaphrodite in the manga, while in the anime it gives no indication of her being anything other than a female. In Saiyuki Gaiden she is Konzen's aunt, and the one responsible for bringing Goku to heaven.

(Source: Saiyuki Wikia)