Rantaro is a student in the Ultimate Academy for Gifted Juveniles and a participant of the Killing School Semester featured in Danganronpa V3: Killing Harmony. He doesn't remember his talent at the beginning of the Killing Game, so his title is the Ultimate ???. When he was first introduced, Rantaro seemed like a mysterious individual. Later it could be seen that he is a carefree and relaxed person. Despite his mysteriousness, he is described as one of the more ordinary students.