Koori was a part of the Arctic brothers. He is more mellow and caring then the other brothers, and he's also second-in-command.
Koori and his brothers first appear when they ambushed Jax. He and Hyoga distract and ran off with his food. He appears later with his brothers when they were attacked by Jax. He was kept back while his brother was pinned down. He tried to resin with him, and was saved by Aotora. He felt grateful and decided to join ohu. His brothers went thrilled at first, but Koori convinces them to join. Koori then returns whatever meat there was left to Jax. During most of the arc, he and his brothers helped their leader gather more males for the final battle. When the invasion began he, Shimo, and Hyoga were chosen as platoon leaders, and invaded the west side of the Gijou. But for unknown reasons, he and his brothers didn't appear in the fight with Aotora and Black Shuck.
he didn't appear during the tundra arc.