Gyūmaō, also known as the Ox-King, is a supporting character in the Dragon Ball series. He is the father of Chi-Chi and the father-in-law of Goku. Formerly the ruler of Fire Mountain, Gyūmaō is known for his immense strength and initially intimidating presence. Despite his fearsome reputation, he is kind-hearted and cares deeply for his family. Throughout the series, he supports Goku and his friends, often providing assistance and comic relief.