Su Zihao, the rich and handsome son of the Su Group, fell in love at first sight with Lin Xi, a newly transferred and aloof schoolmaster, because of a paper airplane prank. In order to get rid of the harassment of many suitors, Lin Xi signed an agreement with Su Zihao - a contract between man and woman.
If one party falls in love with someone else, the agreement will immediately become invalid.
The appearance of substitute teacher An Yu broke this balance, and a rumor of a teacher-student love affair pushed Lin Xi and An Yu to the forefront.
The agreement was subsequently terminated, and Su Zihao's revenge was silent.
An Yu was forced to return to school, and Lin Xi was bullied.
All this changed the life trajectories of three people...
Intention: A white head can't be replaced by snow, meeting each other is already a sign.