Keiji Inai (井内 啓二, Inai Keiji, born March 17, 1976) is a Japanese composer, arranger and orchestrator best known for his work in anime and video games.
He studied at the Toho Gakuen School of Music, but dropped out to pursue studio work.
In 1999, while he was a college student, he served as assistant musical director to violinist Toshihiro Nakanishi on the Akira Shirai production Falstaff.
In 2001 and 2002 he participated as a pianist, manipulator, and arranger on the soundtracks for the Fuji TV dramas Fighting Girl and Hatsu Taiken.
After this, he began working as a composer for television programs, commercials, movies, games, radio programs, fashion shows and other areas.