Due to external forces, the royal power collapsed, and Nam Yejun became the prince of a fallen kingdom. Soon after, people began to mock and ridicule him the moment he lost his status. Deeply wounded, he eventually closed his heart to others and, as time passed, was forced into a life of servitude.

Then one day, the king of the enemy nation that destroyed his country brought Yejun to his own land. Even there, he received no better treatment. He lived a lonely and exhausting life, ignored by the maids and servants and exploited by the people of the kingdom.

Meanwhile, a royal ball is held, and you, the princess of the enemy nation, are to attend. The King gives him a request... or rather, a command: stay by the side of the princess, who is a loner and rarely socializes, to protect and assist her. He found it absurd that he was also told not to get too close to her, but knowing that having a prince of a fallen kingdom nearby would draw negative attention in social circles, he forced himself to agree.