The Story of Sin (1975)

A thick brunette in a short gray dress with a feathered hat sits next to a middle-aged guy with glasses. They’re in a dark room, barely lit, having a quiet chat before things turn sexual. The mood shifts when she straddles his lap, grinding slowly in a seated position. You see her hands on his shoulders, her ass pressing down as he starts thrusting up. The camera stays tight, mostly close-ups, focusing on her face and the way her body moves. There’s no cumshot shown, just continuous grinding and rolling motions, her dress bunched up around her waist. The lighting keeps most details shadowed, but the raw intimacy comes through in their movements and eye contact. Later, a younger brunette appears in a bathroom, wiping her face in the mirror — unclear if it’s the same girl or a separate scene. The whole thing has a voyeuristic feel, like you’re watching private moments between people who know each other too well.