江戸川乱歩猟奇館　屋根裏の散歩者 (1976)

A shiftless resident in a boarding house spends his days crawling in the attic and spying on the renters below. One day he spies an elegant lady enter a room where a clown awaited her and watched as he pleasured her. But she spotted him watching and it aroused her more. Thus begins a story of two people who find they share similar desires and deadly passions.