[3] He studied English literature at Waseda University, but, deciding he could not make a living writing novels, entered Shochiku studio as an assistant director in 1952, and moved to Nikkatsu in 1955.

[6] Nikkatsu gave its Roman porno directors a great deal of artistic freedom in their films, as long as they met the official minimum quota of four nude or sex scenes per hour.

Though his later films took full advantage of Nikkatsu's lenient policies by experimenting with cinematic time and space in an almost surreal manner, his first Roman porno, Wet Lips (Nureta Kuchibiru) (1972), was fairly simplistic.

Japan's most famous sex performer of the time, Sayuri Ichijō,[8] played the title role for which she won the important Kinema Jumpo prize for best actress.

Jasper Sharp writes that Kumashiro uses de Sade's story as a platform for criticizing morality imposed by power, with particular relevance to the censorship trial Nikkatsu was undergoing at the time with the prosecution of Love Hunter (1972).

"[14] Kumashiro also employs censorship as one of the stylistic devices of the film, exaggerating the fogging required by Japanese law by placing black blocks over large areas of the screen.

Red Light District: Gonna Get Out (1974), employing the same setting as Mizoguchi's Street of Shame (1956), illustrates Kumashiro's common use of devices such as internal animated sequences to situate characters, and enka songs to comment on the action.

[15] Kumashiro's 1974 film, Man and Woman Behind the Fusuma Screen: Enduring Skin starred Nikkatsu's reigning Roman porno Queen, Junko Miyashita.

"[13] Roughly one-third of the film takes place in the bedroom, with the claustrophobic atmosphere heightened by such exterior sounds as moaning from neighboring drug addicts, and non-stop rain.

[9] Kumashiro also took breaks from the Roman Porno genre to direct mainstream films, beginning with Bitterness of Youth (1974), a story of student radicalism with similarities to Dreiser's An American Tragedy (1925).

[20] The story, dealing with a Japanese man in Germany and his obsessive sexual relationship with a German woman during Hitler's rise to power, also seemed to echo Ōshima's film.

[13] When interviewed for the British television program, Mondo Macabro, actress Kazuko Shirakawa observed that it may have been Kumashiro's poor physical condition which helped him to portray the fragility of human existence.