Apartment Wife: Night by Ourselves (1978)
A couple lives in a housing complex, but as soon as the wife got married, she became a lazy. The husband keeps asking for sex. The exhausted man spends his days in despair, wondering what the point of marriage is. One day, his wife suddenly dies and he receives an insurance payout of 35 million yen. In an instant, the man became a wealthy bachelor. He was filled with joy and playfulness, but by chance, he became close to a housewife who lived in the same apartment complex and had been interested in him for some time. Unlike his wife, the housewife did all the housework with ease, and she was also kind and accepting of men when it came to sex. Impressed by the idea that she is the ideal wife, he offers to buy her for 30 million yen from her husband...