Co-representative of Signifiant Inc., providing management support for startups and industrial finance services. After jockey school and racehorse training, graduated from the Faculty of Law, the University of Tokyo, and joined McKinsey & Company. Founded Naked Technology while at university and served as its representative; after selling it to mixi, served as mixi's CEO. After restoring performance, stepped down and, following a visiting scholar position at Stanford University, co-founded Signifiant. Also serves as visiting researcher at GRIPS, outside director of Septeni Holdings, and partner at Tokyo Founders Fund. Author of "The Analects, the Abacus, and Me" and "Finance Thinking".