Once the Crown Prince Joins In

Before his rebirth, Shang Junyan's view of Su Xinyi: Despicable and shameless, cunning and deceitful, cruel and ruthless. He dreams of divorcing her.
After his rebirth, Shang Junyan's view of Su Xinyi: Beautiful and kind-hearted, open and upright, full of righteousness. He dreams of marrying her.
Before her rebirth, Su Xinyi's view of Shang Junyan: Generous and understanding, steady and dependable, a true gentleman, worth marrying.
After her rebirth, Su Xinyi's view of Shang Junyan: Petty-minded, pretentious, a real scoundrel, won't marry him even if she dies.
In her previous life, Su Xinyi had a difficult life. She jumped from a countryside girl to the only daughter of the fourth family in Qi Country Duke's Mansion. She lived cautiously and carefully. The other three families of the Duke Mansion coveted her family's property and regarded her, who had returned to her ancestry, as a thorn in their eyes, hating her and wanting her gone.
After getting married, her husband disliked her, her mother-in-law was unhappy, and they forced her to die so that her husband could marry a noble woman. Su Xinyi burned down the Pingjing Prince Mansion, so they could all die together.
After her rebirth, Su Xinyi fears nothing. First, she destroys her own marriage, then she dutifully serves her birth mother, hoping she lives a hundred years. Finally, she repays the Crown Prince's help in her previous life, praising him as a good and generous person whenever she meets someone, helping the poor and uplifting the needy, a great man indeed.
The great Crown Prince: I heard someone is spreading the word that I am a good person.
The Crown Prince, praised into his role, finds out that the little girl who has been praising him is actually meeting someone else for a blind date, a little liar telling lies!
His heart, once black as coal, gradually gains warmth because of her.
In the end, the little liar marries the very successful Crown Prince whom she praised, and her scumbag ex-husband becomes the Crown Prince's servant.