One summer vacation, Yuuya was invited by his mother Naami's friend Yuri to go on a three-day, two-night trip to Tokyo with two sets of parents and children. In fact, Yuuya had been admiring Yuri's beauty and glamorous body for some time. At the inn, he thoroughly enjoyed watching the two mothers change clothes in the nude, and at the mixed-gender hot spring, they washed each other's mothers' bodies. As Yuuya's excitement reached its peak, he sneaked into Yuri's futon to initiate sex, but soon Naami, jealous of Yuri, joined in...
