A young man in his early twenties who, in spite of being an average human being, belongs to the “Superhuman Bureau” and solves crimes. Believing strongly in justice and goodwill, he uses his power for the benefit of society and continues his fight to protect “superhumans.”

An orphan whose circumstances of birth are unknown, he was raised as the adopted son of Professor Magotake Hitoyoshi. Born in the 20th year of the Shinka Era, young Jiro's code of conduct underwent great changes around the 41st year of the Shinka Era and the 45th year.