Expensive Tastes (1978)

Spending freely on the indulgence of self-pleasure!

Home from a date, a couple is brutally attacked in the man's apartment. After the smoke clears, the ashamed woman pleads that the police not be told. A suspicious cop persuades a lady friend to date the same man, and a similar attack ensues. It's revealed that the seemingly innocent man was in on the act, as a clever method to violate women.