I wrote a few posts regarding Nikkatsu censorship in a Facebook group, let me copy-paste them here as well. Most of the content has been discussed here before over the years but maybe this post serves as a quick summary.
Nikkatsu Censorship: Part 1
Some of you may be aware of the censorship case regarding actress Machiko Otani (大谷麻知子)
. Several years ago Nikkatsu pulled all her movies from distribution and ceased sales. Amazon JP listings of old VHS cassettes featuring her have been removed. Several Japanese movie databases (Allcinema, Movie Walker) have removed her name from movie credit lists. All movie director retrospectives held in Tokyo in the last 7 years or so (Noboru Tanaka, Chusei Sone x 2, Kichitaro Negishi) have omitted films Otani is in. Synapse said they tried licensing the Angel Guts series but Nikkatsu wouldn’t sell the 1stfilm because of an actress who appears in it.
The reasons behind this case are not clear to me. If anyone knows, please clue me in. The only piece of info I can find is this Japanese language message board post from 2013, where someone claims he/she saw a message from Otani's family member "about 7 years ago" saying "Otani died deeply regretting her film career".
If that is correct, it would appear her family has requested Nikkatsu to pull her films from distribution. However, I cannot find any confirmation for the claims above, nor for her death.
She had a very short career lasting only about 6 months, during which she appeared in films by several notable directors, e.g. Angel Guts: High School Co-ed (Sone, 1978), Pink Salon: Five Lewd Women (Tanaka, 1978) and High School Girl (Negishi, 1979).
Nikkatsu Censorship: Part 2
Sometime in the 80s the pink film industry agreed to stop exploiting high school girls in pink film advertising. This resulted in many old films being re-titled. Sometimes the results were… ironic. In many titles ”high school girls” (女子高生 or 女高生) became “school girls” (女子校生 or 女校生). Is that any better? The funniest part is that "high school girl” (joshikôsei / jokôsei) and “school girl” (joshikôsei / jokôsei) have the exact same pronunciation. They just replaced the “high” (kô) kanji with the school (kô) kanji. You can see this for example with Angel Guts: High School Co-ed (1978) where the poster spells “High School Girl” (女高生 天使のはらわた) but for the VHS cover it was changed to “School Girl” (女校生 天使のはらわた.
There were other name changes as well. For example “Sailor suits” (セーラー服 / Sêrâ-fuku) became “uniforms” (制服 / seifuku). e.g. Young Girls' Holding Cell (セーラー服鑑別所 or 制服鑑別所) (1982).
It seems the censorship has since loosened since many of Nikkatsu’s Japanese DVD and BD releases have reverted back to the original titles e.g. Lusty Discipline in Uniform (1982) which went from the original theatrical “Sailor Suit” (Sêrâ-fuku shikijô shiiku / セーラー服 色情飼育) to the theatrical re-release “Uniform” (Seifuku shikijô shiiku / 制服色情飼育) and finally back to “Sailor Suit” (Sêrâ-fuku shikijô shiiku / (セーラー服 色情飼育) for its DVD and BD releases.