A bitter love in the past, a half-life marriage contract, and a fiefdom of eight hundred miles, but the promise of death was abandoned? After Emperor Shu's death, the dearest couple have gone through many separations and deaths. Under the beacon smoke and the setting sun, can one of them return as promised? Starting in blood, ups and downs in love; sycamores in the south and trees in the north. She bears the most noble and heavy title of a woman in the world, and she is committed to the monarchs of both countries. The eldest princess, the crown prince, the queen... A hundred years later, the beauty has been reduced to ashes, leaving her name in history. Will she be the demon queen who brings disaster to the country, or is she the heroine of a generation?