He is the husband of his legal wife Ratsetsunyo and mistress Gyokumen Koushu not to mention father of Kougaiji and Lirin. Gyokuman Koushou is the youkai masterminding the revival of Gyumaoh in the manga and anime Saiyuki. Kougaiji is the son of Gyumaoh and his wife, Ratsetsunyo. Lirin is the daughter of the Ox-King Gyumaoh by his mistress Gyokumen Koushou in the manga and anime Saiyuki. Five hundred years before the beginning of Saiyuki, he was a powerful demon lord and he refused to live with humans. Instead he preferred devouring human flesh. His cruel actions lead the gods to send down War Prince Nataku to subdue him. Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. ...
The battle was long and bloody with both sides suffering heavy casualties with Nataku emerging as the survivor and victor of the battle. As for Gyumoah, the gods are believed to have sealed his subdued body together with all the occupants inside Houtou Castle including his son, Kougaiji and wife Ratsetsunyo for 500 Years.
When the sealed was broken, his lover Gyokumen Koushou took steps to revive him. Using a forbidden mixture of science and youkai magic, his subdued body was placed in a special incubation chamber and is now awaiting the Tenchi Kaigen Kyoumon in order to be revived again.