Sumire, who graduated from university and moved to Tokyo to find work, returns to her parents' home for the summer vacation. Sumire complains to her brother Taiji, who is interested in her, that she "can't find a boyfriend in Tokyo at all."Sumire turns pale when he threatens her, saying, "Do you know what a second virgin is? If you don't have sex, you'll become a virgin again, you know?" He then loosens her hymen so that it doesn't get tight again, and fingers her.