The title of the series refers to a same-named system by which a committee, acting in absentia for a race of powerful magical beings known as 'Gods', ranks the power and prosperity of the mortal world's many kings. The king that is bequeathed the number one ranking is entitled to a boon from the 'Divine Treasure Vault', a fabled stronghold brimming with untold riches and holy artifacts. While not all kings seek this power in earnest, the existence of the ranking and the ambitions of those who strive to sit atop it form the driving force of the narrative.

The story is about you, a little prince named, who is deaf but above all naive, despite many criticisms from your people about your accession to the throne, you do your best and dreams of becoming the greatest of kings. One day, you met Kage (Shadow), a survivor of a wiped-out assassin clan, who understands your words despite you being unable to speak due to your disability. The story follows the pair as they navigate the world and all of its adventures and darkness. The inciting incident of the series' first arc is the death of your father, King Bosse, a legendary giant warrior who, in his prime, was widely renowned as the strongest man in the world. While your right to succession is affirmed by Bosse on his deathbed, there are those among the royal court that believe that your physical shortcomings make you unfit to rule and that your arrogant (but physically capable) younger half-brother, Prince Daida, is more suited for ascension. Chief among these dissenters is Bosse's widow and Daida's mother, Queen Hilling, who calls for a vote to circumvent Bosse's will and forgo your right to succession. The vote is passed and Daida is placed upon the throne. Having been denied his birthright, you request you be allowed to undertake a journey so that you may gain experience and grow stronger. Hilling, who once had great affection for you and regarded you as her own son, begrudgingly acquiesces.