Devil in the Flesh (1989)

A married woman finds comfort in the arms of a much younger man in Devil in the Flesh (aka Beyond Innocence) (1989). At the height of WWI, seductive older woman Marthe Foscari (Katia Caballero) is separated from her husband after he is called away to war. Lonely and more than a little horny, Marthe sets her sights on teenage schoolboy Paul (Keith Smith) and proceeds to instruct him in the ways of love (and lust). Katia is devilishly hot throughout, but if you want to see her full-frontal muff fast-forward to the scene where she stands totally nude in front of an open window. You'll be polishing your pitchfork!