Nudity is limited: two scenes of breasts as a woman runs down a road, a few views of male butts, and a full rear view of 8 men and women from a distance, none of these lengthy scenes. Women are seen in bras or non-revealing lingerie several times.
Talk about sex is pervasive, going into some detail. There are many, often lengthy, scenes of simulated sex without nudity, that include talking, moaning, and other sounds, thrusting, etc. These scenes include straight coitus in a variety of positions, cunnilingus, and gay anal intercourse.
As the title implies, themes of sex with or without intimacy, marital infidelity, marriage without love, virginity, and slut-shaming are key to the film.
A prologue scene of attempted sex involves older teens, the rest of the film is about adults.