Ogen was ordered by retired Shogun Tokugawa Ieyasu to lead nine other warriors in a duel against the chosen ten of the rival Kouga Manjidani clan to determine a successor to the shogunate.
As the elderly chieftess of the Iga Tsubagakure ninja clan, Ogen was ordered by retired Shogun Tokugawa Ieyasu to lead nine other warriors in a duel against the chosen ten of the rival Kouga Manjidani clan to determine a successor to the shogunate. She shares a spiritual connection to her hawk which serves as her messenger and servant although it is unknown if she possesses any other abilities. When she was younger, she was very much in love with Kouga Danjo and the two sought peace between the warring clans through their marriage. But following a surprise attack by the combined forces of Oda Nobunaga and the Koga in which her grandfather was murdered, she lost all faith in Danjo.
Despite the Koga's betrayal, Ogen was in her twilight years willing to make her granddaughter Oboro the bride of Danjo's grandson Gennosuke in the hopes that the two of them could bring a definite peace and also find the happiness that she could not. In the manga, Ogen's first candidate was her subordinate Yakushiji Tenzen, yet in the end she preferred Gennosuke as Oboro's future husband.