Born from a mortal mother and vampire father, Song Yuqi is a half breed. She's been on the run by herself since she was 15. She witnessed her mother's murder by his father's clan and since then, she despises vampires even though it's in her own blood. Hiding her real identity, Yuqi now lives among mortals and does things like any other mortals. 

However, half breeds will eventually go through changes in their system. Their vampire self that's embedded in their blood will come out when they turn 19. They'll be forced by their own bodies to fulfill their need for blood. and if they resist, they'll eventually die. 

For the past four years, the girl has been trying to not have any strong relationships with mortals since she knows what's coming for her. Yuqi has sworn to herself that she would never become a vampire no matter the cost. Her 19th birthday is coming in 40 days and she has to fight for herself. 

Unfortunately, things get complicated when one particular mortal boy suddenly shows up in her life.