The Liberty Belles (1973)

Redheaded girl with long bangs and a slim build is on her knees first, taking the guy’s cock deep with her mouth. You can see her throat flex a couple times when he pushes all the way in — messy, wet blowjob with some gagging sounds that feel real. The brunette, short-haired and lean, takes over after, swapping positions with the redhead so they’re both on the bed in matching lingerie. They alternate between sucking him and making out with each other, hands all over tits and ass. Scene starts in what looks like a living room near a piano, flirty conversation, then moves into the bedroom for the full oral session. Camera stays close most of the time, focusing on facial reactions and lip action, not a lot of wide shots or quick cuts.