絶頂姉妹　堕ちる (1982)

Mika, who used to be a call girl, is being pursued by a man that brokers prostitution. Her mother Yoshimi and older sister Mayumi also sold their bodies. But now, Mayumi will marry Soejima, a trading company man. Mika is happy to have a respectable relative and starts a part-time job at a pachinko parlor...