In episode 10, King Desha is the main character. The episode begins in a treasure vault, where King Desha is examining a collection of swords inscribed with glowing runes. A man called the "Ranker" explains to Desha that previous kings selected these swords and that anyone who deciphers the text on them will be granted a wish.

Desha hopes that with this wish, he can restore the humanity of his brother Ouken. However, he discovers that the swords are cursed, as they thirst for blood. The swords begin to decompose in sunlight and require blood to prevent this. Kings who choose these swords are driven to wage wars to quench their blades' bloodlust.

Desha decides not to take a sword and ventures deeper into the vault. Along the way, he passes a corpse believed to belong to a former king. Beyond this point, Desha discovers cells containing demons. In one cell, there is a childlike demon, and Desha decides to make a contract with this demon to fulfill his wish.

As a result of the contract, Ouken regains his humanity—but at a high cost. Desha sacrifices his memories for Ouken's humanity, leaving him confused and unable to remember his identity.

Meanwhile, Despa and Ouken grow worried about Desha as he stops communicating. Ouken decides to enter the vault to find Desha. Inside, he encounters shadowy figures whose identities remain undisclosed, and he also learns that Desha has lost his memories due to the demon's contract.

Ouken then encounters a god-king and fights him. During the battle, Ouken recalls Desha's advice not to fight gods unless there is something valuable to protect. Ouken fights bravely, driven by the desire to protect his brother.

The finale leaves more questions than answers. The purpose of the kings' ranking system, the details of the process, the identity of the corpse in the vault, and the origin of the imprisoned demons remain unclear. Additionally, shadowy figures guarding the vault—one of whom resembles Desha—add to the mystery. The identity of these shadowy figures, as well as the consequences of Desha's deal with the demon, will likely be clarified in the next season.