Hirofumi's acting career took off when he won the role of Sadaharu Inui, the "data-tennis" regular of Seigaku Middle School's tennis club in the The Prince of Tennis musicals, Tenimyu. He became the second actor to play Inui, as part of the second generation Seigaku cast. He made his debut on January 8, 2005 in the Side Yamabuki performance in Osaka. On March 29, 2006, at the end of the final Dream Live 3rd show, he along with the majority of the Seigaku cast, graduated from their roles.