The Dai-bosatsu toge trilogy is based on Kaizan Nakazato's unfinished long series of novels (41 books, written from 1913 to 1941). Set in the last period of the Tokugawa Shogunate, Daibosatsu Toge tells the story of Ryunosuke Tsukue, a nihilistic swordmaster who doesn't hesitate to kill anyone, bad or good.