Summer Children (1965)

On the beach at night, a man and woman are shown making love. The woman's breast is visible briefly. Afterward, she walks away naked, we see a few seconds of one breast again, then she walks away showing full view from behind.

A man later enters a motel room, where he is propositioned by a naked prostitute. Her back and breasts are seen. They have sex.

A man and woman gets amorous but, as she is laying down with only slacks and a bra on, she says she's changed her mind. He then chases her around a bit and gets a rough -- almost to the point of appearing like a rape -- claiming she needs this to get turned on. She appears to then either comply or give up the fight.