Brago is a teenaged mamono with a rough, antisocial attitude. Not much is revealed about his life or personality, other than he resents weakness and especially requiring a human's help to win the demon kingship. He is extremely strong, often defeating other mamono teams without even requiring the use of spells.
His personality softens a bit after meeting with Sherry; Brago is even seen helping a human child. He continues to look down on weaker opponents, however, doing whatever it takes to defeat them. He has a rabid appetite, like most other mamono, once seen eating an entire alligator whole. While he has reluctantly teamed up with Zatch, he isn't above harming Zatch to protect him from greater force, such as kicking Zatch in the groin so he could block a more powerful attack from Maestro with his foot (an action that embarrassed both Sherry and Kiyo).