The title of the film translates as "Deviations of physical love", although the German word "Abarten" covers the whole range from "variation" to "perversion", making the audience wonder what to expect.
The film is a collection of fictional (unconnected) episodes depicting and analysing various forms of sexuality that go beyond "normal" heterosexual relations. The subjects of the four episodes are lesbianism, transvestitism, male homosexuality, and sadomasochism. Some stiff grey-haired academic provides a voice-over and also the analysis between the pieces.
Such academic treatment was often used in Germany in the early 1970s (in the UK even in the early 1990s!) as an excuse to show lots of naked flesh and get away with some softcore rumpy-pumpy. Regarding this film however, it would not be entirely fair to denounce the academic framing as bogus - it simply is part of the sensationalist package, to satisfy people's awakening curiosity about these subjects. From a 21st century perspective, much of the commentary (and quite a lot of the action) appears terribly dated, not to mention that some of the science has not stood the test of time.
The least compromised episode is the one on male homosexuality, although even this has a moment of unintentional hilarity, when the wife tries to rekindle the waning sexual appetite of her husband by wearing the S.H.E. outfit. In a supporting part, this episode also features Werner Röglin in his AFAIK only true-to-live portrayal of a gay man (his campness does not transgress into silliness) - later in the decade he would specialise in the type of gay characters who otherwise only live in jokes of politically incorrect stand-up comedians.
