Yuka Minase and her husband, Koji, visit his parents' home so she can care for his ailing father, Jo. Koji soon returns to work, leaving Yuka alone to tend to Jo. Though Jo has lived in sorrow, unable to let go of his late wife, Yuka gradually finds her feelings for him deepening. What began as mere familial duty transforms into undeniable romantic and physical desire. One day, Yuka receives a call from her husband's mistress demanding she leave him. Overwhelmed and emotionally shattered, Yuka runs from the house, her heart full of forbidden longing for her father-in-law.