Daiya Oowada

The founder and former leader of the Crazy Diamonds, Japan's largest motorcycle gang, and the older brother of Mondo Owada.

Daiya died on the night of his retirement party to save Mondo, who had been driving too recklessly in an attempt to win the race that Mondo himself challenged to. Daiya's dying wish was for his little brother to lead the gang in his stead, and to not let it fall apart.