After receiving an SOS from her son, who had moved to Tokyo, his mother Rena went to take care of him once a month. - However, as they visit each other many times, their love as a family turns into love between a man and a woman, and they end up crossing a line that should never be crossed. - It's definitely not okay to have such a corrupt relationship. - But how can we go back to being normal parents now? - At a loss, Rena's mind comes to the image of her spoiled son. - As a mother, I cannot abandon my child. - Rena decides to go to Tokyo again.