Six-year-old Xia Zhuxin was fostered with her close friend Yan Lang's family because her father was in jail. Uncle Yan and aunt Yan, who cared about her, gave her the love and warmth of her parents. However, her brother Yan Yu, who had an extraordinary IQ and was considered to be gifted, was very cold to her. Not only that, she also accidentally learned that Yan Yu's coldness was not intentional, but a congenital personality defect, a disease similar to Asperger's disease. As Yan Yu grows older, Yan Yu has more and more problems, and Xia Zhuxin's feelings for him become more and more complicated... With the advent of puberty, the seemingly peaceful Yan family becomes turbulent... However, when Xia Zhuxin discovers that everything seems to be her own wishful thinking, everything seems to come to an abrupt end... But you know, you don't know, is it really the end like this? !