Because of the accidental death of his younger brother, he had to separate from his childhood sweetheart and first love, Lu Chuan, and fled the original city with endless pain. Later, he came to Ancheng to live with his grandmother, but unexpectedly met a boy named Gu Nian. This boy showed two small tiger teeth when he smiled. He was clean, warm and sunny. But she was sensitive, quiet, and not good at words. She asked: Gu Nian, why do you like me? He smiled and said: Because you are kinder and more cowardly than anyone I have ever seen. And Lu Chuan, what kind of existence was he? In that memory that was gradually forgotten by time, he suffered alone, and it turned out that he had lost something that he had never had.