Kenzan is Sanjou's partner. Not by his choosing mind you. He's a seasoned Ninja, quick, silent and without remorse. He's a Kitsune, who did have three tails, though he lost almost one whole tail in battle and almost the right in his left eye. He actually used to be a lot like Sanjou, but saw that not taking thins seriously can really get you hurt. Maybe being partnered with the young Tanuki will make him loosen up a little?