(It tells the story of a female killer who was issued a pursuit order and fought hard for 30 days to keep her promise, just to kill the heroine on her 18th birthday.)
He Xiao: 25 years old, 172cm, on the surface he is the lover of the boss of society A, but in reality he is a killer, hand and bodyguard.
Promise: 17 years and 11 months, 166cm, senior high school student.
Purpose: Alternative fulfillment