Giichi Nishihara (西原 儀一, Nishihara Giichi, 1929 – 16 August 2009) aka Shirō Sekiya (関谷四郎, Sekiya Shirō) was a Japanese film director, screenwriter, producer and actor best known for his low-budget and sensationalistic pink films made for his Aoi Eiga studios in the 1960s and 1970s. He has been called both "Japan's sleaziest movie-maker," and "a cult favorite among devotees of extreme cinema."