Miho returns to her husband's home in the countryside. This year, it was my mother-in-law's first Bon festival at my parents' house. My father-in-law, whom I hadn't seen in a while, looked a little tired and a little lonely. However, he showed his strength to his son and his wife as a single man. Miho's father-in-law's masculinity, which is different from that of her husband who is used to the city, and the loneliness that he shows from time to time, really touches Miho's heart. One day, my husband suggested we set off fireworks to cheer him up. The father-in-law's father-in-law, who sees himself wearing his dead wife's yukata and setting off fireworks, is so reminiscent of his late wife that he bursts into tears and hugs Miho. The father-in-law runs into sex with Miho because of the unstoppable emotion. However, the sexual act is different from that of her husband, and Miho, who has felt love for her father-in-law's ex-wife, decides to do it only during this Obon holiday for one week, and although she feels jealous of her husband, she is able to have sex with her father-in-law. There is no stopping the sexual behavior of...