Body Double (1984)

A woman rides a man in forward cowgirl while she giggles and moans in pleasure. We see her fully nude from the front in 3 brief cuts, about a second each. Careful posing conceals their coupled genital areas.

A woman is in the shower with a man, he caressing her body. She is wearing a bikini, and he is fully dressed, but the swimwear's cloth is close enough to her skin tone to imply that she is nude.

A man watches a woman in a lingerie store trying on panties through a gap in the changing booth curtain. She is apparently unaware of his voyeuristic activity.

A man watches a pornographic video on a television. We see multiple women in lingerie, a few with bared breasts, and one wearing nothing but a belt. This latter is shown from the back, so we see her bared breasts, back, and buttocks We hear sexual intercourse in progress, but all action is off-screen; the explicit action is limited to kissing, caressing, and clothing removal.

A man visits a pornographic movie studio whose back-office walls are covered with posters advertising their productions. These mainly show women in lingerie, though there is some implied nudity.

We visit the set of a pornographic movie during filming, but there is no explicit sex, only foreplay and off-screen sounds of sexual intercourse, in the background. Several of the movie-within-a-movie actors are wearing scanty clothing, the most extreme of which is a woman wearing backless leather pants over t-back panties, exposing her bare buttocks while she technically remains not-bottomless.

All scenes of sex and nudity are shown for 3 seconds or less

The reason this is severe is because sex/voyeurism is a large theme in the movie. There are not a lot of sex scenes or nudity

A man spies voyeuristically on a woman in her bedroom using a telescope. She dances in a sheer unbuttoned pajama top, panties, stockings, and high heels. We see her bare breasts several times. She rubs at her crotch a few times after laying down on the bed; in later dialogue, it is implied that she continued masturbating, but we don't see this on-screen.

A man makes out with a woman near a public beach. He undoes her blouse buttons, revealing her low-cut bra and upper breasts. We see a glimpse of her upper areola before she breaks it off.

A man visits a video rental store where a few risqué movie posters advertise adult films. The posters have women wearing only lingerie. The man rents an adult film. The plot continues to extend and reference this porn rental scene.

The whole movie revolves around sex, mainly voyeurism, Hollywood mature audience movie production, and hardcore pornography. There is no explicit sex shown in the movie, but it is implied throughout. The closest we get to anything explicit is a man caressing a woman's breasts and a woman implicitly masturbating through her panties.