Mokuba Kaiba is a fictional character from the anime and manga series Yu-Gi-Oh!. He is the younger brother of Seto Kaiba, the CEO of KaibaCorp. Mokuba is known for his loyalty to Seto and often supports him in various challenges throughout the series. He has a kind-hearted personality and values friendship. In the series, Mokuba is often portrayed as a victim of villains, which leads to his brother's determination to rescue him. He also plays a role in the Duel Monsters card game, occasionally participating in duels and helping to strategize. Mokuba's character adds depth to the story, highlighting themes of family and loyalty.