The existence of the world is always revealed to people in different colors. When the 15-year-old boy stood by the canal in the old city and watched the sun set in the west, he looked childish but extremely lonely. "Children who can't find their shadow know what loneliness is." Lonely people live like trapped animals, with different living conditions, miserable youth years, and the feelings in the world are nothing more than love, family affection, and friendship. The lonely boy travels here, moving forward, living strong, happy and depressed, happy and sad, the lonely Mu Sheng (the protagonist), after going through the hardships of his boyhood, where will Mu Sheng's personal journey go... This is a novel published by the author for the first time in Jingjiang. It tells the whole process of a boy becoming a man, and is about every emotion in the world. The author will take "Blue Sky, Red Sun" as seriously as he takes his own life.