Ryou is the main character in City Hunter, a skilled fighter who has experience as a guerrilla in various conflicts mentioned throughout the show. He was an orphan due to a plane crash when he was a young child, which left him in a rebel village during a civil war and prompted him to learn how to fight at an early age. Despite this, he knows little about his true parentage or birthdate. Kaori Makimura later declared March 26 as his birthday, the day they first met. Ryou came to the United States after the war and worked as a hired gun before moving to Tokyo, Japan where he formed the "City Hunter" team with Hideyuki Makimura. The manga/TV series timeline begins shortly after this formation.