Satoru Mikami, an ordinary office worker, was caught up in an incident and reincarnated into another world as a slime. The unique skill "Great Sage" he acquired at reincarnation evolved into "Wisdom King (Raphael)." As the leader of the Jura Tempest Federation and one of the "Octagram," he has awakened as a True Demon Lord.

A Catastrophe-class dragon whom Rimuru met first upon reincarnating. Known as the Storm Dragon, he was sealed in a cave by a Hero for 300 years, but was released by the evolved Rimuru and Raphael, achieving incarnation using Rimuru's clone as a vessel. With Rimuru's evolution, his abilities have also been strengthened.

The son of the Ogre chieftain whose tribe was destroyed by the Orcs. He has crimson hair and eyes, and jet-black horns. He has a strong sense of justice and confronts unforgivable things head-on. He received the name Benimaru from Rimuru, evolved into a Kijin, and became an ally.

Benimaru's younger sister and the princess of the Ogre tribe. She has light pink hair and horns like white porcelain. Beyond her lovely beauty, she is gifted in cooking and sewing.

A member of the Ogre tribe with purple hair and horns like obsidian. She looks like a cool beauty, but her combat power is extremely high.

One of the Ogre tribe members. He has bluish-black hair, dark skin, and a single pure white horn. He is always calm and collected, specializing in covert operations.

An elderly Ogre who follows Benimaru. Despite his old age, he is a master of swordsmanship.

An Archdemon who rules over the demon race... or so he is classified, but his true identity is one of the seven Primordial Demons in the world.

Ugly, fake-cute, a liar, and manipulative. But maybe her true personality is actually okay...?