Yoohyeon was forced to grow up as a boy and is forced into competing for Princess Minji's hand in marriage.  things go a little different then she expected.    

Seulgi also known as the Winter Queen, she is the ruler of the Four station kingdom, but when her sister disappears and some other mysteries start to happen, she gets involved in an unexpected adventure with the only one who can help her to find her sister, and solve the mysteries, The dancing warrior.