Furin kōkai: Hitozuma midara gai

Original title: 不倫航海 人妻みだら貝

Joji, a nouveau riche womanizer, has returned home after completing a round-the-world yacht voyage. Joji has a son, Hiromi, a civil servant, from his previous marriage. A married woman named Ruriko appears before Hiromi and Joji. Despite being married, Ruriko seduces the single, upright Hiromi. Furthermore, she begins a relationship with Joji, who scolds her for this...