Taxi to the Toilet (1980)

Frank Ripploh is a rascal: he is a shaggy-haired, bearded teacher who is gay and has a very active sex life plus an interest in making films. He keeps his personal life separate from his personal life, though sometimes he corrects student papers in public toilets as he waits to score. He cruises constantly. One evening, he meets Bernd and they become lovers. Bernd is attentive and caring, but Frank gets bored with him and continues his polymorphous perverse ways. How long will Bernd and Frank tolerate each other's habits, and how long can Frank keep his sexual orientation outside of the classroom? Things "come to a head" (no pun intended) during Berlin's annual Queen's Ball and the morning after.