Rimuru is the leader of the Jura Tempest Federation, a nation of monsters. After becoming a Demon Lord, he has built relationships with various nations and factions through not only his immense combat power but also his excellent diplomatic and political sense. He is a figure who continues to develop Tempest amidst international affairs and new exchanges, facing diverse incidents.

Veldora is a top-tier existence with power that shakes the world, a dragon who rules over storms. Currently accompanying Rimuru as a companion, he provides overwhelming combat power and reliable support. While he possesses great strength and majesty, he also has a surprisingly cheerful and playful personality.

Dino is a Primordial being of the Seven Luminaries who governs Sloth and a warrior of angelic origin with top-tier skills. Although he usually appears lazy and unmotivated, he is a powerhouse with hidden abilities and a true identity. He has currently settled down in Tempest.

Ramiris is the Queen of Spirits and one of the oldest Demon Lords, possessing the unique ability to create Labyrinths (Dungeons). She is currently living in Tempest, cooperating with Rimuru and handling the management and operation of the Labyrinth. While she usually acts mischievous and immature, she is an important figure.

Diablo is a top-tier demon known as Noir, the Primordial Black, and one of the strongest subordinates who pledges absolute loyalty to Rimuru. While he usually maintains a calm and dignified demeanor, he becomes more passionate and devoted than anyone else when it comes to matters involving Rimuru.

Milim Nava is one of the oldest Demon Lords, known as the 'Destroyer,' and is a top-tier existence with overwhelming power. Despite her innocent and free-spirited personality, she has formed a deep friendship with Rimuru and is currently active as a reliable ally of Tempest.

Testarossa is originally the Primordial Demon 'Blanc' (White), a top-tier demon possessing brilliant resourcefulness and overwhelming magic power. After swearing loyalty to Rimuru Tempest, she awakened and became an even more powerful existence.

One of the strongest demons, originally the Primordial Demon 'Jaune' (Yellow). After becoming a subordinate of the protagonist Rimuru Tempest, she boasts overwhelming destructive power. Her personality is bellicose and she enjoys battle, but she shows deep loyalty to Rimuru.

Originally the Primordial Demon 'Violet.' Although she uses a calm and elegant tone, she possesses a very cruel and cunning personality. Her combat power is top-tier, and she is a powerful character who skillfully handles poison, curses, and mental abilities.