OVA
Description
Rimuru Tempest originated as Satoru Mikami, a 37-year-old human contractor in Japan. Following a fatal stabbing while protecting a colleague, Satoru reincarnated into a fantasy world as a low-level slime monster. The "Voice of the World" interpreted Satoru's dying words as wishes, granting Unique Skills like Predator and Great Sage. This process erased his human body but preserved his memories and consciousness within the new slime form.
Initially manifesting as a spherical, slightly blue, translucent mass roughly 40 cm wide, this form lacked sensory organs, relying on skills such as Magic Sense for perception. Early survival involved absorbing minerals, plants, and monsters to gain abilities, including Poisonous Breath from a serpent and Sticky Thread from a spider. Rimuru encountered Veldora Tempest, one of four True Dragons, sealed in a cave for 300 years. They bonded, exchanging names: Satoru became Rimuru Tempest, and Veldora gained the surname Tempest. Rimuru consumed Veldora's seal to analyze and break it, storing the dragon within an imaginary stomach for future release.
Consuming the corpse of human summoner Shizue Izawa allowed Rimuru to assume an androgynous human form resembling a younger Shizue. This initial humanoid appearance resembled a six- or seven-year-old child with short hair, typically clad in pelts or simple clothing. Increased strength led to evolution: absorbing the Orc Disaster Geld added 10 cm in height, yielding a nine-year-old appearance with longer hair and silk-steel threaded garments. After the Harvest Festival and ascension to True Demon Lord, another 10 cm height increase resulted in a twelve-year-old likeness wearing a black haori and shoulderless shirt. The final evolution into an Ultimate Slime produced an androgynous adolescent form resembling a 15- to 16-year-old, approximately 160 cm tall, with silver-blue hair, golden eyes, and elaborate black-and-white attire featuring detached sleeves and a golden collar. Explicitly lacking biological sex characteristics across all human forms, Rimuru's genderless nature reflects the original slime biology, confirmed by creator Fuse to avoid narrative complications.
Rimuru's personality blends Satoru Mikami's human ethics with pragmatic monster instincts. Eccentric and playful tendencies overlay strategic analysis and planning. Ruthlessness surfaces when protecting subordinates, leading to torture, memory erasure, or mass slaughter against threats. This contrasts with a core desire to build a peaceful world of harmonious species coexistence. Leadership employs manipulative tactics like forged documents and staged events to cultivate a benevolent image, yet genuine care exists for named monsters viewed as family.
Abilities expanded through predation, evolution, and skill synthesis. The Unique Skill Predator enabled consumption and mimicry, evolving into Gluttony after merging with the Orc Lord's Starved ability, and later into the Ultimate Skill Gluttonous King Beelzebuth upon becoming a True Demon Lord, allowing absorption of matter, energy, souls, and skills. Great Sage provided analytical prediction, skill management, and information processing, evolving into the Ultimate Skill Raphael during Rimuru's demon lord awakening, later gaining sentience as Ciel. Reincarnating as an Ultimate Slime and True Dragon granted Void God Azathoth, permitting reality manipulation. Other significant powers include Megiddo (focused sunlight beams), spatial barriers, universal sensing, and cloning.
Rimuru founded the Jura Tempest Federation in the Great Forest of Jura, establishing a monster nation promoting interspecies equality. Leadership forged alliances with figures like Demon Lord Milim Nava and engaged in strategic conflicts, such as defeating the rogue Demon Lord Clayman, leading to membership in the elite Octagram. Achievements include negotiating human-monster treaties, industrializing Tempest using Earth knowledge, and creating a dungeon managed by Veldora. The ultimate goal remains constructing a discrimination-free society, safeguarded through diplomatic acumen and overwhelming power.
Initially manifesting as a spherical, slightly blue, translucent mass roughly 40 cm wide, this form lacked sensory organs, relying on skills such as Magic Sense for perception. Early survival involved absorbing minerals, plants, and monsters to gain abilities, including Poisonous Breath from a serpent and Sticky Thread from a spider. Rimuru encountered Veldora Tempest, one of four True Dragons, sealed in a cave for 300 years. They bonded, exchanging names: Satoru became Rimuru Tempest, and Veldora gained the surname Tempest. Rimuru consumed Veldora's seal to analyze and break it, storing the dragon within an imaginary stomach for future release.
Consuming the corpse of human summoner Shizue Izawa allowed Rimuru to assume an androgynous human form resembling a younger Shizue. This initial humanoid appearance resembled a six- or seven-year-old child with short hair, typically clad in pelts or simple clothing. Increased strength led to evolution: absorbing the Orc Disaster Geld added 10 cm in height, yielding a nine-year-old appearance with longer hair and silk-steel threaded garments. After the Harvest Festival and ascension to True Demon Lord, another 10 cm height increase resulted in a twelve-year-old likeness wearing a black haori and shoulderless shirt. The final evolution into an Ultimate Slime produced an androgynous adolescent form resembling a 15- to 16-year-old, approximately 160 cm tall, with silver-blue hair, golden eyes, and elaborate black-and-white attire featuring detached sleeves and a golden collar. Explicitly lacking biological sex characteristics across all human forms, Rimuru's genderless nature reflects the original slime biology, confirmed by creator Fuse to avoid narrative complications.
Rimuru's personality blends Satoru Mikami's human ethics with pragmatic monster instincts. Eccentric and playful tendencies overlay strategic analysis and planning. Ruthlessness surfaces when protecting subordinates, leading to torture, memory erasure, or mass slaughter against threats. This contrasts with a core desire to build a peaceful world of harmonious species coexistence. Leadership employs manipulative tactics like forged documents and staged events to cultivate a benevolent image, yet genuine care exists for named monsters viewed as family.
Abilities expanded through predation, evolution, and skill synthesis. The Unique Skill Predator enabled consumption and mimicry, evolving into Gluttony after merging with the Orc Lord's Starved ability, and later into the Ultimate Skill Gluttonous King Beelzebuth upon becoming a True Demon Lord, allowing absorption of matter, energy, souls, and skills. Great Sage provided analytical prediction, skill management, and information processing, evolving into the Ultimate Skill Raphael during Rimuru's demon lord awakening, later gaining sentience as Ciel. Reincarnating as an Ultimate Slime and True Dragon granted Void God Azathoth, permitting reality manipulation. Other significant powers include Megiddo (focused sunlight beams), spatial barriers, universal sensing, and cloning.
Rimuru founded the Jura Tempest Federation in the Great Forest of Jura, establishing a monster nation promoting interspecies equality. Leadership forged alliances with figures like Demon Lord Milim Nava and engaged in strategic conflicts, such as defeating the rogue Demon Lord Clayman, leading to membership in the elite Octagram. Achievements include negotiating human-monster treaties, industrializing Tempest using Earth knowledge, and creating a dungeon managed by Veldora. The ultimate goal remains constructing a discrimination-free society, safeguarded through diplomatic acumen and overwhelming power.