Inumaru (犬丸) is a candidate for King of the Celestial World, who gave Seiichiro Sano his power. The two officially pair up for the tournament when Sano risks his life to save a child from a burning building, and Inumaru does likewise despite Sano's threats to decline being his power user if he tries to help.
Inumaru's credo is that he can not ignore people in danger regardless of the reason, which prompts Sano to join, and to think of Inumaru as his friend rather than his Candidate. In Dougra Mansion, after being told that Sano joined Robert's Ten to save him from the Death Pentagon (a small black bug that Karlpacchio attaches to Inumaru's neck, that would suck all of Wanko's blood out of him on command, thus killing him), he contrives to destroy himself, so that Sano can be freed from his obligation.
He gives Mori her power, thus breaking the most important rule of the tournament (King Candidates can only give one power to one person), in order to force himself to go to Hell so that the others would be saved from certain circumstances that threaten the rest of the Team Ueki. He was later chosen as King unanimously by Team Ueki.