Mr. Mutoh is the father of Amakusa Shōgo and Amakusa Sayo and the husband of Mrs. Mutoh. He taught his son that one day he would be a leader responsible for bringing salvation to the oppressed Christians of Japan. He is killed after the family's affiliation to the Christian faith is discovered and later on his wife is killed too, leaving the two children orphans under the care of his brother-in-law Nishida Hyōei. His words swell deeply in the heart of Shogo, who later begins taking revenge against officials of the Meiji Government responsible for murdering innocent Christians in Japan.