Eun Lee has had an eventful day. First, she won the lottery. Then, she was summoned to a mystical realm by the Demon King, Kaon Mahana Lord Moon Blood Rain, and was newly named Rue, princess of the demon realm. Eun demands to be returned to her original world so she can collect her winnings, but Kaon wonders if she has something to do with his late lover's will. Eun surprises herself by adjusting to her new and unfamiliar life, but will she ever truly let go of her past and find happiness here?