During summer vacation, Erina, a female university student, returned to her hometown. Suffering from the intense heat and drenched in sweat, she learned that her family's bath was out of order and, following her mother's suggestion, went to borrow a bath at her grandfather's house in the back. The grandfather, shaken by Erina's sensuous growth, which they had not seen for a long time, could not suppress the strong desire that surged up after decades and attacked Erina in a fit of passion. Then, he exploited her vulnerability, saying, "In such a rural area, if rumors spread just a little, your mother and others might not be able to go outside..."
