Once upon a time, there was such a fool. She didn't know how to take care of others, let alone herself. She didn't understand life, youth, or love. In her world, everything is simple and pure. And next to every fool, there will always be such a smart person like him... When she slowly left her footprints in his heart, she didn't know anything about it, she was just so stupid. He said: Little fool, I seem to like you a little bit. She was so frightened that she didn't know what to do... Four years later, she was no longer the fool she was back then. He still loved her, but she had... This feeling could only be remembered in retrospect, but it was already at a loss. Who is the real fool?