I have several minds about this movie. It has an excellent story (based on a French novel) involving a poor but handsome young rogue who worms his way into the wealthy family of a boorish school chum and seduces all the female members. But the material REALLY requires a stronger actor who can pull off charismatic and malevolent effectively. However, this movie is saddled with Kevin Bernhardt , a typical 1980's blow-dried pretty-boy with all the charismatic malevolence of a European C. Thomas Howell. Some of the other flaws are not necessarily the fault of the original filmmakers. Cheesy English dubbing NEVER helps a halfway serious movie, but a subtitled version of this movie is not currently available. There also seems to be some strange law that "erotic" movies MUST have a sub-Kenny G soft jazz score, but I can tell you that if this kind of horrid music swelled up every time people started having sex in real life, I personally would just stop doing it!
If you take this movie as sex movie though, as opposed to a serious drama, it is actually pretty effective. The female cast is superb. The very sexy Lydie Denier plays the bitter, wheelchair-bound older sister. Denier would eventually go to Hollywood where she was almost completely wasted in bad horror movies and American "erotic thrillers". Veteran Eastern European exploitation actress Eva Czemyrs plays the mother. She is both sexy and quite BELIEVABLE (for a change) as the middle-age mother of adult children (although frankly she is way too quickly and easily seduced by her son's friend). The never-to-be-seen-again Marie Bossee is effective as the whiny girlfriend of the rich kid, who the rakish protagonist seduces and abandons (literally) by the side of the road. Veronique Beguin is not entirely believable as the adolescent younger sister, but that was probably necessary since she has a very hot and quite perverse sex scene where the protagonist teaches her how to masturbate and takes racy nude pictures of her. It's certainly not boring as far as the sex goes!
You could certainly make a better, much more serious movie with this material, which is kind of a cross between "Dangerous Liasons" and "Boudou Saved from Drowning" (later re-made in Hollywood as "Down and Out in Beverly Hills"), but it does work well as a softcore sex film. Interestingly, one of the better "erotic thrillers" of the 1990's "Poison Ivy 3" (aka "Violet") was almost a verbatim re-make of this film, but with gender roles switched. The two films share an almost identical twist involving the family maid (the one sexy female here the protagonist does NOT seduce), but the European class-consciousness works better in this French movie, even if Jaime Pressley (the star of "Violet") is far more sexy and believably malevolent than Bernhardt. This obviously could have been better, but it's not bad for what it is