From 1971 to 1988, Nikkatsu studio’s Nikkatsu Roman Porno label for soft-core adult films was a training ground for young directors who went on to have thriving mainstream careers. Such filmmakers include Shusuke Kaneko (“Death Note,” 2006) and Yojiro Takita (“Departures,” 2008). The label also generated films later regarded as classics.

Hideo Jojo’s latest films, “S-friends” and its follow-up “S-friends 2,” are both produced by Nikkatsu but are not revivals of Roman Porno, which catered to the tastes of male audiences, not infrequently with lurid scenes of sexual abuse. Rather, they are based on a manga series by Yoriko Minato targeted at women.

A prolific maker of films with an erotic edge, including the charming “Love Nonetheless” and the skin-crawling “To Be Killed by a High School Girl,” Jojo directs with an affinity for his female-centered material and discretion in its many sex scenes, which are steamy but not crudely exploitative.