Return of the Secret Society (1968)

AKA Babette

Babette, a bisexual, is an active member of “The Secret Society,” a sex club for unusual and bizarre sexual practices. Ramon, leader of the club, begins to compile a library of pornography that the club plans to sell to interested purchasers. Babette meets a married couple who reveal some new techniques in the art of triangular love. She then responds to an advertisement and becomes one of a group of four who explore a wealth of sexual possibilities.