She is the young marquis of the Yun family. When her mother was four months pregnant with her, her father died in the border battle. From then on, the emperor oppressed her and the Yun family was "exiled" to Anyue City. In order to keep her father's title, her mother had no choice but to let her disguise herself as a man. He, the young master of the Jun family, came to Aoxi Country alone when he was fifteen years old, met the ten-year-old "him", and became sworn brothers. But since when did his feelings for this little brother become more and more wrong?