Kuroma Tatsushiro

Kuroma is the antagonist of Naruto Shippuden: Ryujinki. He is a young man with gray hair and green markings on his face. Like Akari, whom he supposedly has an unknown connection to, he has red eyes and small horns on his head, signifying a connection with the five dragons that he apparently summons. He has what appear to be several explosive, summoning, or sealing tags on his robe, and a large weapon or summoning scroll strapped to his back with a dragon's head on one end. The light green medallion on his belt matches the one Akari wears around her neck, and presumably furthers their connection to the dragons. Currently, any other information, including the true nature of his and Akari's connection to the dragons, is unknown.

Trivia

 * "Kuroma" means "pure black." This is in contrast with Akari's name, which means "light."