Chūsei Sone (曽根 中生, Sone Chūsei; 1 October 1937 – 26 August 2014) was a Japanese film director known for his stylish and popular Roman Porno films for Nikkatsu, particularly the first two installments of the Angel Guts series. Despite a somewhat uneven career, many mainstream critics consider Sone the best of Nikkatsu's Roman Porno directors.
Source: “Chūsei Sone”, English Wikipedia (CC BY-SA 4.0), excerpt