Third Master Su, also called Su San, is the prefect of Xingyuan Prefecture and the third son of the Xuanning Marquis Manor. He is aware that Su Ningxin is actually former Imperial Concubine Chen and treats her with great respect and caution. He is a cautious official, understanding the emperor's arrangements and the implications for his career. He is ambitious but not bold, and he follows the emperor's design to be transferred to Jiangning. He tries to maintain a normal father-daughter relationship while avoiding suspicion. He is present at the coming-of-age ceremony and supports Su Ningxin against Madam Zhao's accusations. His personality is somewhat anxious around Su Ningxin due to her palace background.
