AU idea where Yi-kyung is part of the Korean royal family, and upon the untimely death of her parents, she is taken in by her child-less aunt, the Queen (who wants to make her crown-princess).
But behind the facade of the beloved, fashionable and cheerful princess, she has horrible anger issues and has killed enough people to know she likes the feel of it.
Kyung-yi is her bodyguard, who has to keep her from killing, but never able to go the public in fear of destroying the royal family's image, losing her job, her life and perhaps her loved ones.