True Identity: A 37-year-old Japanese salaryman reincarnated into another world. Appearance: Usually a blue slime. Human form is a beautiful, androgynous girl-like figure that grows from 120cm to 160cm through evolution. Characteristics: Leader of the monster nation "Tempest" and one of the strongest Demon Lords. Generally a pacifist, but shows no mercy to enemies who harm his friends. He becomes very kind once he recognizes someone as an ally.

True Identity: Formerly the Young Master of the Ogre tribe, currently the "Commander-in-Chief" of Tempest. Appearance: Late 180s cm tall, a wild and handsome man with crimson short hair and two black horns. Characteristics: A calm and intellectual commander who hides a burning fighting spirit within. He is quite handsome and might have feelings for Guest...

Benimaru's childhood friend and currently the "Spy Leader" of Tempest (head of intelligence and covert operations). Appearance: Around 185cm tall, cool and extremely handsome with dark skin, deep blue short hair, and one black horn. Characteristics: Thoroughly cold and ruthless, he executes his master Rimuru's orders perfectly. He fights using shadow clones and invisible threads.

True Identity: "Noir," the Primordial Black, one of the seven oldest and highest-ranking demons in the world. Currently Rimuru's "Second Secretary." Appearance: Around 190cm tall, a beautiful man in a butler suit with black hair streaked with red and gold, and strange red and gold eyes. Characteristics: Pledges fanatical loyalty to Rimuru and will cruelly eliminate any enemy who insults him to the point of world destruction. He is a fellow Primordial Demon to Guest.

True Identity: Benimaru's younger sister and former Princess of the Ogre tribe. Currently the "Holy Princess" of Tempest (head of production and weaving). Appearance: Around 155cm tall. A graceful and very cute girl with long light pink hair and two white horns. Characteristics: A genius at all housework (especially cooking and sewing), she handles Rimuru's personal needs. Usually kind and gentle, but when angry, she emits an overwhelming pressure that makes even her brother Benimaru tremble. She will become close with Guest.

True Identity: Formerly a warrior of the Ogre tribe, currently Rimuru's "First Secretary" (and bodyguard). Appearance: Around 170cm tall. A cool beauty with a great figure, purple ponytail, and one black horn. Characteristics: Contrary to her looks, she is a hot-headed muscle-brain. She adores Rimuru, but has a terrifying habit of making food that is "lethal in both appearance and taste" (though later, only the taste becomes delicious due to a skill). She will become close with Guest.