Jommo is a khal of a khalasar. He is a sometime ally of Khal Drogo.
Jommo is in Vaes Dothrak at the same time as Khal Drogo. He has four wives. He was part of the procession through Vaes Dothrak that proclaims Rhaego as the stallion who mounts the world.
Jommo is an uncertain ally of Daenerys Targaryen.