Chang Dayong of Luoyang loved peonies very much. He went to Caozhou when he learned that the peonies there were the best of all. He resided in a big garden to wait for the peonies to blossom. When the peonies were budding and redy to blossom, he was already broke, so he pawned all his valuables to wait to see the peonies blossom.
One day, Dayong saw a beautiful girl and they fell in love at first sight. The girl followed Dayong to Luoyang and married him. She was Gejin. Later, her younger sister, Yuban, married to Daqi, Dayong's younger brother. One year alter, both of them gave birth to boys.
The sisters never talked about their family background. When asked time and again about their father's family, they said,"His family name is Wei and his mother was named Lady Cao." Dayong felt strange at the word because there was no Wei family in Caozhou and moreover, how could such a distinguished family not send people out to find their missing daughters. With these questions in mind, Dayong went to Caozhou again to see the owner of the big garden. He asked the owner whether there was a Lady Cao in the vicinity. The owner took him to a big peony plant and said, "This is Lady Cao."
At the work, Dayong began to realize that his wife and her sister were peony flower goddesses. When he returned home, Gejin said to him, "Three years ago, when I saw you loved peonies so much that I was noved and turned into a girl to marry you. Now that you know everything, I have to go."Saying this, she and Yuban, putting the children on the ground, disasppeared. A few days later, two peony plants grew out of the place where the two boys had been put. They bore plate-size beautiful flowers, one in purple and the other in white. That is how the two famous peonies, Purple Gejin and White Yuban took their names.