The story focuses on the three-year high school life of high school girl Cheng Ruohan. It mainly shows that Cheng Ruohan has been under tremendous psychological pressure since she entered the H City Key High School Experimental Middle School as a self-funded student. Not only did she make little progress in learning, but she also did not know how to deal with the interpersonal relationships between classmates. Except for her friend Murphy, who grew up together, Cheng Ruohan rarely communicated with other classmates. By chance, after meeting Ji Yu, a top student in the same year, life turned a new page. Ruohan gradually finds the direction and meaning of her efforts, and she hopes to become better for the people she likes. At the same time, she discovered that she did not know all the secrets of her good friend Murphy, and felt that she should readjust her requirements for friends and constantly update her definition. Ruohan studied hard in order to be admitted to Ji Yu's experimental class. After entering the experimental class as expected, he found that Ji Yu had transferred to another school. However, Su Jingyi, the first girlfriend who broke up with Ji Yu, failed the college entrance examination and came to Ruohan's experimental class. Due to some misunderstandings, Su Jingyi and Ruohan did not get along well, and Ruohan and Murphy were no longer close. Just when Ruohan decided that high school life was a dead end, Ji Yu came back again. Su Jingyi wants to get back together with Ji Yu, but Ji Yu seems to have someone else. Ruohan wanted to know if that person was him. In the tense senior year of high school, Ruohan was worried about his studies, but he was also concerned about whether his sincerity would be rewarded.