Ryohei begins living with his wife and her parents. However, due to his poor health and inability to work, he is treated coldly by his wife and father-in-law. At that time, only his mother-in-law, Erika, treats him kindly. The presence of his kind, busty mother-in-law. At first, Ryohei is genuinely grateful for this ray of light, but as he gets closer to his mother-in-law, his reason gradually begins to crumble...