Nankobou Tenkai is a senior political advisor and strategist serving Tokugawa Ieyasu in the period immediately after Japan’s Sengoku era. He holds a position of power within the shogunate and is deeply suspicious of the rival Iga and Kouga ninja clans, viewing their superhuman abilities and centuries-old vendetta as a threat to the newly established Tokugawa rule. To neutralize this danger, Tenkai devises a manipulative scheme: he orchestrates a formal contest in which each clan must send five of its best warriors to fight to the death, believing that the resulting bloodshed will weaken both sides and end their potential as instruments of rebellion. Cunning, calculating, and ruthless, he acts without hesitation to sacrifice the ninja for political stability. His primary motivation is the consolidation of the shogunate’s power, and he carries out this plan with cold precision, showing no regard for the personal cost to the participants. Tenkai’s relationship with Tokugawa Ieyasu is that of a trusted, influential subordinate who helps shape the shogun’s decisions, though it is Tenkai who pushes the deadly contest forward. He has no direct combat abilities; his strength lies in political manipulation, foresight, and his willingness to set tragic events in motion. Throughout the story, he remains an unwavering antagonist, and his actions directly spark the conflict that drives the protagonists into a devastating clash between love and duty. There is no significant character development for Tenkai; he serves as the architect of the tragedy, a fixed figure whose scheme ultimately succeeds in forcing the clans to turn on one another.