Virgin Hostage (1972)

From the Something Weird Video site:
“After a long day working for the Ice Capades (!), all SUZANNE FIELDS and her girlfriend want to do is relax at home with a nice take-out chicken dinner. Unfortunately, a trio of crooks on the lam have other ideas for our heroines, bust into the gals’ apartment, and hold them hostage.

Then gang leader Dan leaves to take a walk (!!) and lunatic Willie decides to sample Suzanne’s mouthwatering wares. Suzanne’s none too thrilled by this — you see, she’s The Virgin Hostage — but, soon enough, she loses her cherry to Willie, as well as to Dan’s Ed Norton-esque brother, Roger, and eventually Dan himself.

The girls’ pals, Bob and Betty (whose mini doesn’t even cover her ass) finally show up with a chicken dinner and Willie forces them to fuck, too! But Dan’s conscience suddenly kicks in and he wrestles the gun away from Willie, beating the greasy creep for good measure, and offers a half-hearted apology to the ladies (“It’s okay!”) just before the film runs out.

This is probably the only porno in which its characters don’t want to get laid. Even the men have to be forced at gun point and seem pretty angry about it: “You’ll get yours for this!” The Desperate Hours this isn’t.”