Age: 15 Hometown: Tokyo, Japan Yuu Arimura was the center of the famous idol group "Mr. Doctor." Although he was active in the entertainment world from an early age, Yuu was impressed by the race he saw for the first time at the racetrack he visited for work, and took an entrance examination for a horse racing school. His stage name is Yuu Otonashi (音無 優). (Source: Official Site, translated)