Kang Seulgi as Aerith/Aerin Zoe she has a secret identity that she doesn't even know who's parents have been killed at young age and decided to be moved to other country for fresh start but then when she turned 17 she decided to go back to the place where she was born to start new things, explore, heal her self and maybe finally found a new friend other than her friend Yuki who's she've been friends ever since childhood and moved out after the tragedy that happened to her family.

Gong Seungyeon as Yuki Izumi a full blood vampire training partner of aerin and closest friend ever since childhood.

Bae Juhyun as Bella Snow a secret daughter of the owner of the most popular school Smallvile she is also a popular president of the school with brain and looks specially a good personality that every girls envy and will change aerin's life .

Aerith's father a secret agent and own the biggest secret company who fall in love with a vampire girl and married her, aerin's mom the vampire girl join her husband as part of being a secret agent and work together for many years until a tragic happened when aerin is at age of 8 .