The story tells the story of the country's attack on Guo and the doctor's advice on the relationship between the two countries as close as lips and teeth. My lips died and my teeth were cold, but I didn't listen to advice and was finally destroyed by gold.

This allusion comes from Zuo Qiuming's Zuo Zhuan, which was published in Xi Gong for five years. Later generations used it to describe the close relationship between the two sides, sharing weal and woe.