There are four great powers in this world, occupying the four directions of southeast, northwest and northwest respectively. Beichen is in the north, Nanyuan is in the south, Yunshang is in the west, and Zuodu is in the east. Originally the four countries were of equal strength, but later the gap became wider and wider as they annexed smaller neighboring countries and developed their national strength.
The story revolves around the love between the Nanyuan Crown Prince and the Crown Princess, and tells several different love stories.