Karion

Hundreds of years ago, he became a new generation Demon Lord recommended by Milim and Kazaream, and is a lion beastman known as the Beast Master. He overthrew his half-brother Gradim, who had killed the previous king, with the help of the three beast warriors of that time, and became the king of the nation of Eurazania.

He is honest and straightforward, but impulsive and instinctively seeks strength. At the beginning of the story, he agrees with Clayman, who aims to expand his own power and create a Demon Lord that can be manipulated, and sends Phobio to the Great Jura Forest to investigate the forces that subdued the Orc Lord in Volume 3. He meets Rimuru when he comes to retrieve the rampaging Phobio, thanks him for the rescue, and recognizes the Jura Tempest Federation as a friendly nation, initiating trade. In Volume 5, he is defeated in a duel by Milim and taken away by Frey, but cooperates with Milim and Frey's plot by pretending to be dead. At the banquet of the Demon Lords in Volume 6, he admits that he lacks the capacity to be a Demon Lord and steps down from his position to become a subordinate of Milim.

After becoming Milim's subordinate, he participates in the martial arts tournament of the Jura Tempest Federation as "Lion Mask," but forfeits in the second round against Gobta and later joins Gobta in training. In Volume 14, he trusts Milim and has a good conversation with Frey, aiming to reach higher together. In Volume 15, he joins Frey in the battle against the Eastern Empire, defeats Gradim, and evolves into an Awakened Demon Lord by obtaining the souls of Gradim's subordinates, becoming a higher holy spirit of the light attribute, the Light Spirit Beast. In Volume 18, he makes the awakened power his own in Ramiris's labyrinth, and in Volume 19, he becomes the supreme commander of Milim's forces, taking charge of the entire army.