Ryo was 23 years old when he became a Dairanger. In his daily life, he was an apprentice-cook at a Chinese restaurant in Yokohama's Chinatown. His dream was to be the number-one Gyoza cook in all of Japan. He was a direct descendant of the Dai Tribe. Ryo had an eight-year-old sister, Yoko, who was born around the same time their father supposedly died.
Ryo was taking out the garbage when a Baron String captured his friend Yumi, and he gave chase. It was then he encountered a RyuseiOh, and was recruited to become the next RyuRanger. While confused at first, he quickly took on the responsibility and went with the other three Rangers to recruit Rin, which in the process led to the Dairangers working together for the first time to defeat Baron String.
Eventually, he met someone who was Jin, a gentleman assassin who had a penchant to kill martial art masters. He was a mix between everything Ryo wanted to be, and everything that he feared. But Master Kaku warned Ryo to stay away from Jin, who had no access to Ki-power, because he believed Ryo would be defeated if he challenged such a master.