A detective, often nicknamed 'The Defeated Detective', who has keen insight on mysteries. He was saved from death by Inga prior to the start of the series. He made a deal with Inga before the series started, in exchange for Inga not killing anymore people, Shinjuurou will be asked the question, what his soul really says, he said no under the influence of Bettenou and had to use it to get out of the illusion. At the end of the prequel movie, he is given a new persona by Kaishou Rinroku. It is unknown what his name was prior to the story.