The youthful past between a sixteen-year-old boy and a young female English teacher. The story tells that Liu Xiyu, a high school student who loves novels and music, wrote a novel in class, but was confiscated by the new English teacher Yang Jie. By chance, Yang Jie learned about Liu Xiyu's wish to learn French, but for some unknown reason, she made an agreement with him to teach him French in the playground after school every day. Naturally, the two opened up their hearts, talked about each other's lives, and gradually developed a secret love. However, facing each other's teacher-student relationship, they can only suppress each other's undercurrent of emotions. However, when two young and lonely hearts collide, where should they go...