The "L/R15" project to make two sex comedies with an R15 classification, given to films judged inappropriate for viewers under the age 15, brings together the talents of Hideo Jojo, an award-winning specialist in adult films, and Rikiya Imaizumi, a maker of light dramas about the romantic troubles of young urbanites.

The first to be released was “Love Nonetheless,” which was scripted by Imaizumi and directed by Jojo. For the second, “Straying,” the roles were reversed, with Imaizumi directing and Jojo scripting. Both films, however, feature a black-and-white cat.

The feline plays a central role in “Straying,” though this film is not one of the many in Japan targeted at cat lovers. It has Imaizumi’s signature touches, beginning with a romantic roundelay that verges on farce, while comically revealing its four principals’ foibles. Though it offers up fewer laughs than “Love Nonetheless,” the film is more knowing about the ways sex can complicate and clarify relationships.