Doryuu

Doryuu (弩竜) is a character who appeared in All-Star Taimanin.

All-Star Taimanin
Originally a Ryuumon executive, after a CD virus incident destroyed his organization, Doryuu left and led a gang of his own named after himself. He was pursued by the allies of Gaiza Nisha, who then defeated him in a duel and made him his escort.