Yesung is a vampire send to the human world to achieve his task. The task he has to carry out from his father, the king.
He is sent to a foster family where he gets to know Ryeowook, the youngest son. He wants to open up but that is difficult because he has to keep his real identity hidden. Ryeowook is a kindhearted, handsome boy who becomes fascinated by Yesung. He doesn't understand why he's so standoffish.

He may resist Yesung's bite, but can he resist his charms?

But there is one rule, vampires can't fall in love with humans, because if they do and they kiss, they lose their powers and they will be banned from the vampire world.

Will he be caught Kissing with the vampire?