Genpachiro Hotta, along with the nun Katsuki, a petty thief, and Hira Shichi, a former lock-picker turned prison guard, once saved a woman from harm. However, this woman was brutally murdered later on, prompting them to swear vengeance at her gravesite. From that point on, the four of them, as shadowy assassins, began eliminating wrongdoers to help the souls of those who had met untimely deaths find peace.