Aya married a man who had a child from a previous marriage. She was enjoying a happy life with her already grown-up son, Yuya. However, she was beginning to feel lonely and unfulfilled by her indifferent husband's relationship... Then, her husband was sent on a long-term business trip, and she and Yuya started living together unexpectedly. They suddenly became strangely close, and Aya started to feel uncomfortable as he started to get more physical with her. She tried to distance herself from him, but Yuya started to approach her more and more boldly...