Chen Yu is deaf, and his schoolmate Zhou Jiji is mute.
In such a big Wu Qingli, they were the only ones like this, they were in the same school, and they both had accidents when they were young and became like this.
So one can only speak but not listen, and one can only listen but not speak.
They seem to be a perfect match.
However, Chen Yu has always only heard of Zhou Jiji but never seen him.
... Until one day after school, she saw Zhou Jiji squatting under the thirteenth staircase.
Concept: Life is limited, emotions are unlimited