Ten years ago, Xu Zhao Su, who had a congenital heart condition, and Xu Qing Yu lived together in an orphanage and were close friends. Later, Xu Zhao Su had an unexpected encounter with Cheng Xiao, a blind boy from a neighboring convalescent home. Using the names “Mo Mo” and “Xiao Feng,” the two supported each other. Cheng Xiao gave Xu Zhao Su half of his family's jade pendant and promised to stay together for life. When a fire broke out at the orphanage, Xu Zhao Su rescued Cheng Xiao and Xu Qing Yu from the scene. Due to a moment of malice on Xu Qing Yu’s part, the rescue team missed the best window to save Xu Zhao Su. In critical condition, Xu Zhao Su donated her corneas to Cheng Xiao. After Cheng Xiao regained his sight, he was forcibly taken away by his family, and the two were separated, with their whereabouts unknown.