Much of the finale centers on Kouji, the step-son of Sumie. By this episode, both Mitsuko and Sumie are involved in an affair with him.
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"He thinks I am weak," she said, her voice steadying. She walked to the window, looking out at the impenetrable grey mist. "He thinks I will drink the tea and fade away quietly." Much of the finale centers on Kouji, the step-son of Sumie