The Ishikawa household appeared to be happily married. Yuna, a full-time housewife, had a secret past—before marriage, she was involved in an affair with her current husband's boss. Unable to let go of those feelings, she quietly harbored her longing throughout her daily life. Then one day, a sudden reunion with her former lover reignites her suppressed passion. Though both are now married and unable to face the truth honestly, they surrender to primal instincts that override reason, repeatedly indulging in the forbidden fruits of love.