Mika works as a life insurance lady. Although she had been living a life of misunderstanding her husband, Mika, who was in the prime of her women, was seeking men and secretly serving her "sex sales" without telling her about her. He met a young man named Kiyoshi, who was more than a year older than him, and he was particularly physically compatible with him, and he began to meet him frequently. The relationship between what is called a sex friend. One day, Kiyoshi was giving a passionate speech to his friend, saying, "If you're going to be your sex friend, a mature woman is definitely the best!" The reason is...