This is the first novel I wrote. It starts with the heroine Jieyun meeting her first love Qin Huai four years ago in the subway. Just saying "How are you?" Gently staggers the time of four years. The subway starts, carrying the old past and driving away. They have never seen each other again. They have their own lives and their own love. They are busy with their own careers and each has their own emotional destination. However, a certain For a moment, when the train was moving away again, Qin Huai looked at it from a distance, and his heart was touched by something unknown, with a faint pain. There are too many regrets in this world, and people's hearts are broken. For the sake of responsibility, we would rather compromise and be sorry for ourselves than hurt her again. Qin Huai said: "I have already failed one woman, and I can't let down another one again."