Also known by her childhood nickname Nannan and referred to as Young Master Si. She is actually the daughter of Great General Si Gongzhen but disguises herself as a man. She is currently a notorious young wastrel, though as a child she was merely mischievous. She fell gravely ill after being frightened by blood splattered on her face when she and Xiahou Jin discovered an infiltrating spy, causing her to lose many memories. Her martial arts skills are slightly above average, barely enough to fight Shou Yi to a draw. She is deeply embarrassed by her mother's matchmaking attempts and fears exposure of her true female identity, which would be a crime of deceiving the emperor and give leverage in the struggle for the imperial throne.
