Birth date: April 23
Yuuya Daigo is the captain of Magami High School's Wrestling Club and is skilled in hand-to-hand combat. Outwardly he appears to be hardened, but actually he is rather sensitive and honest. Despite his sports background, he enjoys cooking and aspires to go to a culinary college. He has a deep sense of justice, and dislikes frivolous people, like Kyouichi seems to him. Yuuya has a major crush on Komaki Sakurai, and tries hard to please her (by cooking elaborate meals) and stay by her side.
Yuuya keeps his past to himself - until it comes back to haunt him. He had a difficult time in middle school after his mother passed away. He hated his professional father, which led him to become a delinquent and brutish thug; he even had a faceoff with Kyouichi during their younger days on the streets. Although it is never discussed in detail, Yuuya was trained by the Shinto priest Arai, who seems to know about the high schooler's Star of Fate and the on-going struggle they all face.
He sometimes fights with magical chains, kept wrapped around his arm. In the second season, his Star of Fate is revealed as Byakko, the Vessel of the White Tiger, and Yuuya is the first to metamorphose into the deity, much to Komaki's distress.
Yuuya is a descendant of the Buddhist monk Yuukei Daigo from the game Tokyo Majin Gakuen: Gehouchou.
(Adapted from Wikipedia, Japan Wikipedia, and original video game data)