When she was six years old, she saw him for the first time, with a bright smile that made her feel dazzled; he saw her for the first time, with sweaty hair sticking to his face and a few beads of sweat on the tip of his nose, so he gave her a white handkerchief. From then on, he called her "Yaya".
When he was seven years old, he entered elementary school and left. He gave her a rag doll that looked like her, and then said a bunch of strange things, but she only remembered the sentence "I will come back to see you, Yaya."
From then on, she looked forward to the boy who called her "Yaya" every day to come back to see her...
Nine years later, they were admitted to the same key high school from different places. One entered the school from the left and the other from the right of the school gate. Although they both recognized each other, neither of them spoke. What had changed?