In Period of Attachment (1975) AKA Go On Your Own Way.

In Period of Attachment, ERIC EDWARDS, sporting a Warren-Beatty-in-Shampoo-look, and his busty wife, LISA MARKS, feel left out of that "hip, happening, 70’s swinging scene." After a banging that’s as hot as Satan’s asshole, they decide to mutually see other people. ("See"? Don’t they mean "fuck"?) Highlights include: Eric having blue flame sex with a hot filly who turns out to be his friend’s wife (!) who recommended her to begin with (!!); Miss Marks eating a black dude’s chocolate mousse on a shag rug; and lesbian action with photographer ROBIN BYRD that delivers the goods in "Cuntachrome." Then a cute JOEY SILVERA and his gal pal read Forum Variations, looking for new deviate sexual roads. "How ’bout sticking a high heel up your ass?" she asks, "Suck my dick," is Joey’s reply. (Hey, can’t argue with logic!) Eric and his wife spy on the action as Joey gives the brunette a spanking before a spunking. Eric and his lady finally come of "bond"-age as well!