Under the rift of the Blue Era, the land of Atlanta, where humans and elves coexist, is on the verge of fragmentation. Lin Ye, a 16-year-old useless alchemy apprentice, accidentally awakened the ancient star soul from the ancient book left behind by his grandfather - a pure white elf larvae who called himself the "first generation contractor". When his fingertips touched the star pattern on the elf's forehead, a forbidden prophecy deep in the continent suddenly emerged: "The day when the twin star souls return to their respective places, the roots of the World Tree will hang upside down."
In order to find out the truth behind his parents' disappearance, Lin Ye was forced to embark on a journey to find seven star soul fragments scattered across the continent. On the way, he met the wolf-eared elf girl who guarded the holy spring with a blade, the blind prophet who used the stars to predict the future, and the cursed mechanical knight. However, as the contract deepened, Lin Ye discovered that his soul actually resonated with the destruction elf "Dark Ember", and the seemingly righteous Holy Church was using human sacrifices in an attempt to resurrect the ancient evil god.
When the last fragment shattered in the bloody moonlight, the branches of the World Tree began to engulf the city. Lin Ye held the blood-stained alchemy staff tightly and looked at the lines of light and shadow intertwined in his palm. He finally understood the true meaning of the prophecy - the so-called "twin star souls" never choose light or darkness, but let the two forces reach a balance in the palm of his hand. A contract battle that rewrites the fate of the race begins under the broken star dome!
