An ordinary white-collar worker in the city travels to a strange country, an imaginary history. She opened a shop to get rich, and thought she would have a stable life, but instead she became the daughter of the prime minister and helped the Ninth Princess seize power; he was a noble prince who went to the border town to fight on the battlefield, but he fell in love with her for the rest of his life. They don't want to live and die vigorously, they just want the water to flow slowly and know whether they are warm or cold.