Duke of Xu was the current Duke and the maternal uncle of Prince Heng Guang. He had watched Prince Heng Guang grow up and understood his temper very well. He was one of the founding nobles who remained highly influential, along with the Duke of Zhen. When Prince Heng Guang was furious about Wen Yuesheng's actions, Duke Xu advised him to avoid the storm, saying that she was just a princess and there was no need for the prince to be so upset. He suggested waiting until the storm blew over before discussing other matters. Duke Xu also served as Prince Heng Guang's father-in-law. He intervened just in time during the court session, making a quick gesture to an official nearby. Despite his advice to step back, Prince Heng Guang's grudge with Wen Yuesheng had already been formed and would not end peacefully.
