Tenkai Nankoubou (南光坊 天海, Nankōbō Tenkai) is a High Priest of the Tendai Buddhist Temple and Political Adviser to the Tokugawa Shogunate.
Tenkai has the appearance of a short bald old man being almost 107 years old with large burrowed white eyebrows that cover his eyes usually and matching white goatee. A large beak like nose and wears typical monk garbs consisting of a dark robe and darker obi wrapped around his waist and gold and yellow shawl stringed shawl around his neck.
A Tendai Buddhist monk and political adviser for the Shogunate. Tenkai was the one who suggested to Ieyasu that since the Tokugawas are a military family, the succession dispute should be settled though some sort of organized duel between ninja instead of valued samurai. As the duel between the Kouga and Iga rages on, Ieyasu sends him into the inner castle to keep the peace between Ofuku and Oeyo. He later returns in Basilisk's sequel series, .