A pair of world-famous lovers who share a life-and-death bond, because of a one-month vow, hold hands together and never leave each other, wandering around the world, home and country. One is a princess who is living in the world, with stunning beauty and peerless martial arts skills, and the other is a handsome and free-spirited prince who was abandoned by the country and possesses world-class talents.
A pair of twin brothers who were born into noble families, due to a decision made by their mother, have been separated from each other since then. Because of the blessing of fate, the elder brother became a noble prince looking down on the world. Because of the abandonment of fate, the younger brother became a knight-errant who dominated the world.
The brothers reunited more than twenty years later, but it was on a bloody battlefield, all because of a deeply loved woman. Brotherly love, son-daughter love, which one is longer and which one is shorter? Where will he and she go?