Shi Yu, the eldest daughter of the Shi family in the capital, is renowned for her gentle nature. On the day of her arranged marriage, her fiancé stands her up. To silence the gossip, she turns around and takes the marriage certificate with Shen Duchuan, the boy next door from the Shen family who has just started college and has called her “big sister” since childhood. Everyone thinks it’s just a temporary fix and waits to see when this “older woman, younger man” marriage will fall apart. Shen Duchuan dutifully plays the part of her “contract husband”: quiet, obedient, and careful not to cross the line. Until, at a party, rising movie star Lu Jiangwan declares his love for Shi Yu in front of everyone and asks why she left without a word all those years ago. In an unnoticed corner, Shen Duchuan corners Shi Yu in the restroom, his eyes burning with ten years of possessiveness. “Big sister, the contract never said I had to deal with your ex for you.”
