Miho Tono returns to her husband's rural hometown for Obon, where she reunites with her father-in-law, who seems tired but tries to maintain his masculinity around them. As they spend time together, Miho notices a mix of strength and loneliness in him that contrasts with her city-raised husband. One day, her husband suggests they watch fireworks to cheer up. When Miho sees her late wife's yukata being worn by her father-in-law while setting off fireworks, an emotional wave washes over her, causing tears to fall. Her father-in-law embraces her tightly, unable to control their feelings any longer. Their intimate encounter carries a different tone than those shared with her husband; Miho feels the love her father-in-law has for his deceased wife throughout their passionate week-long affair during Obon vacation...