[1] As a teenager during World War II, Kobayashi was involved in anti-war activities, resulting in his torture by the Japanese military police.

[4][5] In an interview with the Director's Guild, Kobayashi claimed that it was this first-hand experience with torture that gave him his interest and adeptness with the sado-masochistic genre of pink film in which he often worked.

[1] Here he worked under ero guro masters Teruo Ishii and Hiroshi Shimizu, as well as Kinuyo Tanaka, Japan's first female director.

[1][6] For Shintoho Kobayashi made ten more films with such exploitable titles as Dangerous Temptation, Three Women Burglars and Phantom Detective: Terrifying Alien (all 1960).

[13] Kobayashi made a major miscalculation by attempting to deal with a socially significant theme in Impotence (不能者, Funosha) (1966).

"[14] Typical of early pink films, the camera-work in Impotence makes careful use of camera angles and props to imply more than is shown.

A story of romance between the girls and guests at a hot spring resort, the film's freshness and freedom was in welcome contrast to Impotent's heavy-handed moodiness.

[2] Kobayashi directed Matsui again, with two other prominent pink film actresses of the time, in Pleasure of a Bitch (あばずれの悦楽, Abazure no Kairaku) (1967).

He directed Roman Porno Queen Junko Miyashita in her film debut in I Lost Control of Myself Like This (1971).

[18] Other titles Kobayashi made for Tōkatsu include Pervert's Pitfall and The High School Girl Who Likes to Be Watched (both 1976), Peeping Assault (1977) and Looking from Below (1981).

During the "Big Bust Boom", in the wake of Kimiko Matsuzaka's February 1989 debut, Kobayashi directed several films in that genre.

[3][19] Kobayashi also directed prominent post-Kimiko Matsuzaka era big-bust performer Shinobu Hosokawa in two films, Big Tit Soap, Come in the Valley!

Together with Ishii, Kobayashi was able to persuade Michiko Maeda, who had been banned from Japanese cinema 42 years before, to make her come-back appearance in the film.