Kenta, a young pianist who has just lost his job, is drowning his woes at a bar, when he meets a man in a Hawaiian shirt named Yamaki. He invites Kenta to work with him, and the next thing he knows, Kenta wakes up to find himself in a room he has never been in before. It is a strange room that seems to have no connection to life. He descends a staircase to find many shelves of books.
In war-torn Japan, the Tokugawa Shogun, desperate to restore peace to his people, orders the assassination of the hostile warlords. A beautiful young woman is raised from birth with nine other orphans, to become an assassin. Her name is Azumi, the ultimate assassin.