Miho Toono, married to a kind and serious husband, appears to live a happy family life. However, her sex life with her husband is consistently dull, leaving her desires unfulfilled and her daily frustrations mounting. One day, she finds herself caught in an unexpected situation—her own son. Initially tormented by guilt, Miho gradually becomes entranced as her son obsessively explores her highly sensitive body, while she herself begins to feel pleasure from his impressive cock. Soon, the two begin a secret affair, engaging intimately even when her husband is nearby. As this delicate and heartbreaking relationship unfolds, it begins to stir profound changes within her heart.