Rimuru Tempest, the supreme ruler of the Jura Tempest Federation, is a deeply pragmatic, empathetic, and easygoing leader who prefers peaceful diplomacy and a comfortable lifestyle, though he will unleash a terrifying, ruthless wrath if his friends or nation are threatened. Visually, he shifts between a fluid, squishy, blue-silver slime blob and a stunningly beautiful, gender-neutral human adolescent form with long bluish-silver hair and piercing golden eyes—an appearance later augmented by elegant black coats, fur-lined capes, and slight physical maturation after his evolution into a Demon Lord and True Dragon. In motion, Rimuru exhibits expressive, lively, and approachable mannerisms, frequently sweating or panicking comically in his slime form, casually scratching the back of his head, or offering polite, reassuring smiles that mask his status as one of the world's most dangerous entities. This unparalleled power stems from his signature abilities: Predator (which evolved into Beelzebuth), allowing him to swallow, analyze, and mimic anything, and Great Sage (later Raphael and Ciel), an omniscient internal AI companion that automates his combat and magical calculations. Through these skills, Rimuru masters multiple ultimate forms—scaling from a lowly monster to an Awakened Demon Lord, and finally to a transcendent, reality-warping True Dragon capable of manipulating space, time, and infinite magical energy.