My life has never been the same since then. Our father and mothers death changed our lives completely. A Brother and Sister experience a harsh childhood after seeing their father get infected with something that they dont even know about. After a few years later the brother and sister both go their separate ways. The older brother name Park Ji Sang becomes a Doctor traveling around the world saving lives and the little sister Park Ji Choa has a secret that she hide from her brother is that she's actually a undercover detective along side another Vampire named Kang Joon. What'll happen to both Choa and Ji Sang relationship between the two siblings? Who will become the trator and who will become the savor?