A fictional South Korea that follows a constitutional monarchy. Labeled as evidence of infidelity, the youngest princess, Lee Shin-ah, gets caught up in the suicide of a student at the same school. With the help of a newly appointed escort, Han Tae-kyung, she manages to clear her name, but continues to fall into an unknown conspiracy... Mysterious enemies threatening the royal family, a sweet and bloody romance between Shin-ah and Tae-kyung that blossoms amidst the tension.