Athlete Su Xiao is transported into her favorite comic, becoming the heroine, Su Xiao. However, her love interest is stolen by the villainous sister, and she is betrothed to the unwanted Prince Rui. Refusing to follow the original story, she fights to change her fate, outwits her rival, and unexpectedly finds love beyond the pages.
More than 900 years ago, the mermaid princess Ao Fan Fan was rescued by the scholar Huo Yun Shen, and so she was determined to commit herself to him when he reaches 25 years old. The strange thing is that Huo Yun Shen has lived in every life and died mysteriously before the age of 25 every time. In this life, Ao Fan Fan went ashore earlier to find Huo Yun Shen.