Miyaji is known for his work at Gamearts, a company that he founded at the age of 19 with his brother Yoichi Miyaji. He worked on a number of Gamearts classics, including Silpheed (PC, Mega CD), Gun Griffon (Saturn), and the Grandia series. In 2000, he formed G-Mode.
G-Mode did not share the circumstances of Miyaji's death. Taking his place as CEO of G-Mode will be Ryu Okoriyama CEO of Gaia Holdings.[/p]