Bulgasal plot
Dan Hwal was born with a curse. During the Joseon dynasty, when he had to wipe out the remains of the previous dynasty as a soldier, he suddenly became immortal. For 600 years he can neither kill nor be killed. He is a Bulgasal, a mythical creature that feeds on human blood. Dan Hwal suspects who is behind his curse and wants revenge. While hoping that one day he will be freed from the curse, he crosses paths with Min Sang-woon. Like him, she was immortal, but after a tragic event she has turned back into a human being.