Prince Ojin is a Professional Duelist, celebrity, and member of the royal family of the kingdom of Misgarth who Dueled against Sartorius in the Genex Tournament. He gloated that he would defeat Sartorius with one attack, but was defeated himself before Sartorius' first turn even came. Upon his defeat, he fell under Sartorius' influence and provided him with the control switch for his laser satellite cannon. He returns later in the tournament to retrieve one of the switch's keys given to Jaden Yuki by Sartorius' good personality, but fails despite aid from The Light of Destruction. While Jaden and Sartorius face one another in their final duel, Ojin falls under Sartorius' control once again, and is successful in arming the satellite cannon.
Ojin is aided by his trusted secretary Linda, who has served Ojin since his childhood while she then served as a maid in his parents' house. They shared a special bond that provoked Ojin into taking the blame of breaking his father's scepter so as to save Linda from being fired. But because he had no other friends he often cried at night when he went to bed, and Linda was aware. When Ojin lost to Jaden, he felt abandoned by his so-called friend Sartorius, but Jaden made him realize that Linda had always been by his side as his true friend, and Ojin apologized to Linda for never realizing how much they meant to each other.
He is later chosen by Sartorius, possessed by the Light of Destruction, to turn on the satellite. Linda and Hassleberry chase after him but are too late.
His name is meant to be a pun, as "ōjin" is the Japanese word for "royal person".