Ryūji Kiyosu is an fourteenth year old boy. He wears a long sleeve t-shirt and a long pants. He was Shinkalion Dr. Yellow Driver Pilot.
A 14-year-old teenager from Nagoya who willingly signs up with The Shinkansen Ultra Evolution Institute: Nagoya Division to be a fully trained Shinkalion Driver, and is by far, effectively the eldest of all under-aged Drivers to be recruited into the institute.
Ryūji is the son of Chikuma Kiyosu, who like Hokuto Hayasugi, is also a core developer of the Shinkalions; making Ryūji of similar background as Hayato. But unlike Hayato, Ryūji was a highly disciplined karate martial artist who had the potential to champion competitions, but dropped out of continuing the art to tend his family due to the death of his father, and hospitalized ill mother. In order to aid his late father's passion for Shinkalions, along with the hopes to earn some financial security from the institute, he voluntarily signs up to be trained as a professional Driver.
His N700A Nozomi specializes in close-range combat with high-powered Bare-Fisted Monk abilities; his Shinkalion also possesses a unique transformation power-up to enhance his abilities output, add Ryūji's own martial arts skills for boost makes his Shinkalion's overall performance near impeccable.
Ryūji is the oldest of three children, and he enjoys teasing his younger siblings Tatsumi and Miyu. However, he is on good terms with both of them. This might imply that Ryūji and Tatsumi are became Dr. Yellow Pilot and N700A Nozomi Pilot respectively.
In the series
He shares the same voice actor with his father Chikuma Kiyosu.