The reincarnation of Sirix's precious wife, Serena. Yuuma is an arrogant yet good-natured boy. Though he is male, he still retains Serena's feminine face, and hates this about himself. His dream is to became a "manly man" so people will stop mistaking him for a girl (which Keidai had done upon their meeting). Yuuma develops a crush on Mii Serizawa, Keidai's best friend, early on in the series, though doesn't plan on confessing because he knows that Serizawa likes Keidai. Though he claims to dislike Keidai, the truth is he really is unsure about his own feelings. When Reina Sakakibara is introduced, they clash very often because of their identical appearances and personalities.