Su Lanxin is Su Ningxin's half-sister, the daughter of Concubine Zhao. She is envious of Su Ningxin's position as the legitimate eldest daughter and the potential marriage to the Duke of Zhenguo's household. She schemes to frame Su Ningxin by arranging a false encounter with a strange man (Chu Jihan) at the coming-of-age ceremony, using a handkerchief and invitation. Her plan is clumsy and easily seen through by the adults, though she persists out of desperation. She is impulsive and not very shrewd, revealing her emotions in her gaze. She is a competitive younger sister who acts out of jealousy.
