Mu Chenghe, a doctoral student in the Department of Physics at East Lake University, misunderstood Xue Tong, a junior student in the Department of English, for cheating in an exam during a temporary final exam. Since then, the two have been "indissoluble". In the interaction between you and me, Mu Chenghe and Xue Tong fell in love with each other and started a romantic love story of two-way secret love. During college time, Xue Tong met three roommates: the cold and beautiful Zhao Xiaotang, the lively and enthusiastic Bai Lin, and the quiet and gentle Song Qiqi. The four girls with different personalities experienced various love stories while gaining friendship. From school to society, from family to work, despite joys and sorrows, the four girls have their own growth and gains. Some people leave forever, and some things come to an end. Good friends and lovers are still around, and the past days have become eternal and exclusive memories.