Kannon
One of the five great Bodhisattvas dwelling in heaven, Kannon presides over mercy and compassion—though she's best known for being crude, irreverent, and unapologetically sexy about it. She's portrayed as a hermaphrodite in the manga, though the anime downplays this entirely and presents her straightforwardly as female.
Kannon's the one who sent Sanzou and his crew west on their journey. While she seems to enjoy throwing obstacles and trials their way, fans often note that her behavior masks genuine long-term investment—for the past 500 years, she's been watching over Goku and the others with real care. In Saiyuki Gaiden, she's revealed as Konzen's aunt and the person who originally brought Goku to heaven.
Her actual power level is something of a mystery. She casually knocked out Goku even after he'd transformed into the Seiten Taisei, which suggests she might be stronger than she lets on—possibly stronger than anyone else around.
Content compiled by AnimeList.moe from publicly available sources.