Formerly Satoru Mikami, he was stabbed by a random attacker in the real world and reincarnated. After receiving various abilities, he became a slime and woke up in a cave. There he met Veldora the Storm Dragon, who was lonely and trapped in a magic spell called Unlimited Imprisonment. They became friends, and since naming requires magicules, Veldora named the slime Rimuru Tempest, and Veldora took the name Veldora Tempest himself. Rimuru then used his Predator skill to take Veldora into his body (just storing him). Upon leaving the cave, he met Goblins who asked for help. He went to their village, where the Elder asked him to fight the Direwolves. He accepted, and after the Direwolf leader died, the son became Rimuru's subordinate, ending the conflict. Later, Rimuru interacted with humans and met Shizue, eventually gaining a human form. He was ambushed by Ogres, but after winning, he learned their village was destroyed by Orcs and it was a misunderstanding, so he helped them. He fought the Orc Disaster Geld (an evolved Orc near Demon Lord level) and kindly consumed everything to end the battle. He worked to get closer to the mastermind Clayman, but one day while Rimuru was away on diplomacy, the village was raided by humans, and many Goblins and his secretary Shion were killed. Devastated, Rimuru destroyed the human army and summoned a demon who became his ally, named Diablo. He then evolved into a Demon Lord using the souls. His initial skill, Great Sage, evolved into Raphael and resurrected Shion and the others. He later attended Walpurgis, the banquet of Demon Lords, where Clayman tried to frame him, but an angry Rimuru presented evidence and defeated him. Afterward, he negotiated with the Western Holy Church, leading to a duel with Hinata Sakaguchi. It was revealed the Seven Luminaries within the Church were the true enemies; Rimuru and Diablo cooperated to defeat them. After forming ties with the Tengu and others, he held the Tempest Founder's Festival to interact with various nations. While strengthening ties with Western nations and building the country, the story shifts toward conflict with the Eastern Empire, focusing on the war against the Empire. As Tempest develops and diplomacy with other nations progresses, the story moves toward the final stages of the Imperial War.

Boisterous and deeply emotional.

Calm, cool, and taciturn.

Gentle and refined.

Possesses a strong sense of responsibility and bravery.

Cheerful, energetic, and free-spirited.

Calm and polite.

Confident and composed.

Elegant and calm.

Boisterous and cheerful.