The story of Cow Gourd comes from the heroine "Zhen Xuan" in the kung fu film Empress. Whenever people ridicule someone who is about to have a black belly and do bad things, they will use the sentence "XXX is now a cow gourd XX". For example, Niu Luyou Zhen Xuan, now everyone calls a person Niu Luyou so-and-so, which also shows that a person has changed from a harmless white rabbit to a powerful role.
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It turned out that Zhen Xuan was a pollution-free white rabbit when he first entered the palace, and he was often retaliated by An Lingrong. Later, under a series of stimuli, Zhen Xuan turned black. At that time, in order to let an abandoned princess return to the palace, the emperor tried his best to give Zhen Xuan a new identity, calling her Zhen Xuan.