31-year-old Li Qinai woke up from a dream and felt that the growth process of a girl was like a battle in a dream. At each stage, you will encounter a boy blocking you. They may be annoying people who play tricks on you, or they may be stinky boys who like you but dare not say it. They are like the devil in video games, always creating difficult problems to block your path to growth. The biggest roadblock is the boy you like the most. They suddenly appear in your life, give you a world, and then take that world away. They make you grow up overnight, become the mark of your growth, and then become your big devil. They will suddenly appear at any moment in your life when you are unprepared, give you a heavy blow, and laugh at you for wasting your efforts... Qinai's big devil is her boyfriend when she was 17 years old - Dai Haian. Haian is the first boy that Darling fell in love with, and the first boy who made Darling see another side of the world. Their youth was brilliant and their love was beautiful, until time gradually caused cracks in their relationship. They found that they were never the same people. A free boy met a girl who needed a sense of security. Two completely different people were in the same love, and the final ending was always sad. After the breakup, Darling grew up gradually. Today, at the age of 31, she has a stable career and a stable boyfriend. Everything seems to be fine, until a serious car accident made Darling see the little Haian of that year. Everything suddenly changed. She began to gradually find that everything was not what she thought. The seemingly stable life and relationship seemed to hide Darling's true desire for life. What does the appearance of little Haian represent? What do you want at the age of 31? Is it a farewell to past love? Or uncertainty about the future? This is a story about women's growth, about gender issues, and about how time changes people. At the age of 17, we can fall in love as long as we are happy. At the age of 31, when the ex-boyfriend and girlfriend meet again, can the life that women want and the promise given by men still be synchronized?