Guwon

Gu-won is a powerful demon who has lived for over 200 years. He makes contracts with desperate humans, granting their wishes in exchange for their souls when the contract ends. He lives luxuriously and runs the Sunwol Foundation. He is arrogant, confident, sarcastic and treats humans as temporary, insignificant beings. He meets Do Do-hee, a wealthy heiress and CEO. At first, they dislike and distrust each other, but Gu-won becomes interested in her because she isn't afraid of him. During an attack, Gu-won saves Do-hee, and his demon tattoo mysteriously transfers from his wrist to hers. Because of this, Gu-won loses access to his powers unless he is physically connected to Do-hee. He therefore has to stay close to her to use his powers. He protects her from people trying to kill her and repeatedly uses his supernatural abilities to save her.