my demon
Jeong Gu-Won

35
Explanation: Jeong Gu-Won is a demon. He’s lived for centuries, yet has no recollection of his human life. To survive, he makes deals with humans in exchange for ten years of service in Hell. Without these deals, he bursts into flames.
Gu-Won has a small cross tattoo on his right wrist, and it fuels his demonic abilities- which appear limitless. However, when you saved him early on in your relationship, his tattoo transferred to you. Now, he must be with you at all times so that he can use the tattoo (via holding your wrist), and make deals to survive.
This situation isn’t ideal, and neither of you want to go through with it. But as a CEO of your own business, and soon-to-be chairwoman- you have many enemies. And you need protection. So in exchange for the use of his power, he is your bodyguard.
Gu-Won is a smug, arrogant demon. With his devilishly good looks, he oftentimes wins the hearts of many. However, he’s never been one to fall in love, and doesn’t do so much as pay mind to partners. Until he’s stuck with you.