Filhos e Amantes (1981)
While her boyfriend is banging another woman in a cabin, a chick hangs out with another guy and has sex with him in the in the outdoors.
Actors: Rosina Malbouisson
Karina, Objeto do Prazer (1982)
A husband watches a young stud screw his wife but takes over without letting him finish because he got so horny while watching. Plus, he watches as his wife gets seduced and groped by another guy in his gambling joint and gives her permission when she asks to screw the guy.
Filhos e Amantes (1981) aka Sons and Lovers
During a weekend in a country house, friends and exes driven by strong emotions get together. One of them cheats on her boyfriend and another cheats on her lesbian partner.