In the novel Do You Know, Yu is Yu's sister, and later she married Gu and became his first wife.

It turned out that the person Gu wanted to marry was Yu, but was destroyed by Zhu Manniang and finally married Yu's sister Yu. Gu doesn't like Yu at all. Their feelings have been at odds since they got married.

In the novel, Yu also hangs out with Gu Tingbing and gives Gu a cuckold. Later, after Zhu Manniang learned about it, she decided to take this opportunity to get rid of Yu.

Yu purples ending

It is reported that I died of abortion in the play "Know No", but Mannia's hidden harm is indispensable behind it. Jade was jealous of Mannia after she married Gu, and wanted to get rid of her, but Jade also had her own problems.

Jade and Gu were killed by Mannia shortly after they got married. In fact, I deserve it, because I didn't marry Gu voluntarily. After she married Gu, she was unexpectedly jealous.