A Wedding Invitation

High school sweethearts QiaoQiao and Li Xing are about to graduate from university when Li Xing surprises QiaoQiao with a marriage proposal. QiaoQiao declines, offering rash arguments as to why she's not ready, unaware of the devastating secret that would have ended their relationship. They write a break-up contract: if they're both single in five years, they'll get married. Five years pass, and Li Xing invites QiaoQiao to his wedding, prompting her determination to win him back at any cost, despite the lingering secret.