Su Nianyou, a sophomore student in the Department of Chinese Language and Literature at Xingmang University, is a cute and delicate "dessert girl" who is good at handicrafts and writing. She secretly recorded "Heartbeat Diary" because of her crush on the male protagonist. She was slightly inferior and sensitive in the early stage, but later she grew into an independent literary creator with the encouragement of the male protagonist.
Lu Shiyan, a junior in the Department of Computer Science at Xingmang University, is recognized as the "school-level scholar". He looks cold and taciturn, but is actually gentle and careful. His hidden skill is the piano. Due to family reasons, he is a little slow on relationships, but he pays special attention to the heroine.
