One of the early racers from Saitama to compete against Takumi with his turbocharged Levin, Wataru appeared later in Fourth Stage, this time swapping the turbocharger for a supercharger to achieve more linear acceleration. A skilled driver, Wataru refined his abilities on the perilous Shomaru Pass. He traveled to Gunma seeking new racing challenges and to keep an eye on his sister Kazumi, who had just started working at a hotel with her aunt. In episode 9 of Fourth Stage, Wataru reappeared as Nobuhiko's cousin, watching Takumi race against the Northern Saitama Alliance in hopes of spotting a weakness.
Later, Wataru faced off against Keisuke Takahashi in a wet weather race. However, during the race, his tires lost traction when they touched a metal gutter while he was adjusting his wipers, leading to his defeat.
Some time afterward, Wataru encountered an impostor Project D in Saitama and helped the genuine Project D expose them as frauds.
(Source: Wikipedia)
