The Liberty Belles(1973)

Saga of a man who wants to publish his novel. The plot line revolves around Roland's unpublished novel "A Woman in a Web". Helen is a domineering type who scoffs at the idea of even looking at the dog-eared manuscript, but when Theresa becomes simpatico with Roland she kindly forwards it to her boyfriend, who scores a big publishing deal. After many sex scenes the cast of six all get together for a finale orgy, though it is staged strictly two by two (all in the same living room) rather than group sex per se.