The legendary continent of Ao Tian is divided into four countries: Southeast, Northwest, Northeast, and Southwest. The strongest soul masters in these countries are called "Dukes", and each country has seven Dukes. The inheritors of the Dukes are called "Apostles", representing the pinnacle of power in each country. This grand and complex story begins in the western kingdom of the Aslan Empire.

An honest and humble civilian boy named Qi Ling is inadvertently drawn into the empire's conflicts. Although he has never received any soul master training, Qi Ling is told that he has been chosen as the Apostle of the seventh Duke, and now must follow his Duke into life-or-death situations. The powerful soul masters that once only existed in people's imaginations now constantly appear before Qi Ling, and the hidden animosity between the rulers of the empire gradually emerges.

After experiencing countless thrilling battles, Qi Ling is separated from the prince who was once inseparable and dependent on him. He returns to his loneliness...