Yuri has no children and lives happily with her husband Kiminori, who is often away on business trips. One day, Akiko from the Miyashita family next door tells her that she and her husband are going on a trip to Europe. Yuri is envious of the elegant Miyashita couple, but she offers to take care of the Miyashitas' only son, Takashi, at her house... And on the day of the trip, Takashi comes to Yuri's house. Yuri is excited, because she had heard that Takashi is a virgin...