Momoka Kagura is kind, thoughtful, serious, and so devoted that she would reject the relationship if she knew her boyfriend was married. Taking advantage of her feelings, he lies that he is single and begins dating her. When she grows suspicious because they rarely meet, he deceives his wife and takes Momoka on a secret hot-spring trip to keep her happy. Surrounded by steam, he plans to spend the entire night embracing her unique K-cup curves, fucking her until she is completely attached to him, while she remains unaware that she has been drawn into an affair.