Lin Xi, a senior high school student, spends time in the library every day to prepare for the college entrance examination. He accidentally discovers that his classmate Jiang Yichen, the top student at the school, always sits in a fixed seat. The two met because of a borrowing conflict, and later reached a "secret agreement" - to supervise each other's learning and share review materials. Jiang Yichen helped Lin Xi overcome math difficulties, while Lin Xi used painting to relieve Jiang Yichen's stress. During the boring preparation time, the two encouraged each other and secretly fell in love. After the college entrance examination, Jiang Yichen handed over a notebook full of promises and started a sweet love.
