anime "That Time I Got Reincarnated as a Slime"

Octagram Members
Rimuru Tempest: The newest member of the council. He appears as a genderless teenager with silver-blue hair and golden eyes.
Guy Kimson (Lord Rose): The oldest and one of the most powerful Dark Princes. A tall man with defiantly fiery red hair, scarlet eyes, and an athletic build, he wears revealing, luxurious clothing. He possesses an arrogant, yet charismatic and calculating personality.
Milim Nava (Destroyer): She appears as a short teenage girl with pink hair in twin tails. She wears a very revealing black suit. In reality, she is a powerful half-dragon with colossal destructive power, a capricious demeanor, and a kind heart.
Ramiris (Labyrinth): The Fairy Queen. She appears as a tiny pixie (the size of a palm) with butterfly wings, green hair, and eyes. She is loud, boastful, and comical, yet loyal to Rimuru, and rules over a vast underground labyrinth.
Luminus Valentine (Queen of the Night): The true ruler of the Holy Empire of Luberius. A graceful vampire with heterochromia (her right eye is red, her left is silver-blue) and long silver hair. She dresses in a gothic black-and-white French maid dress or royal attire. She is cold, majestic, and secretive.
Daggruel (Wrath of the Continent): A giant of the titan race. He appears as a huge, muscular man with dark skin, a stern face, and short dark hair. He possesses a calm, noble, and honest character, holding back an army of giants.
Leon Cromwell (Platinum Saber): A former human and "Summoned Hero" who became the Prince of Darkness. He is an incredibly handsome man with long platinum (golden) hair and stern features. He wears shining golden armor. He appears cold and ruthless, but he pursues a noble goal: finding his childhood friend (Chloe).
Dino (Fallen Guardian): A fallen angel. He appears as a young man with tousled purple-blue hair and lazy, half-lidded eyes. He dresses in simple, slightly casual clothing. He is the laziest person.

Other Races and Key Allies
Geld (Orc Lord): A huge, hulking orc with gray skin and a massive shield. Silent, incredibly hardworking, and loyal. He leads Tempest's construction and engineering forces.
Gobuta: A small, green-skinned goblin with a perpetually silly expression and a quiffed hairstyle. Despite his comical appearance and laziness, he possesses a genius intuition in combat and quickly masters complex techniques.
Gabiru: A lizardman (draconian) with green scales, wings, and a tail. He loves pompous speeches and adores being praised by his subordinates. He oversees cave exploration.

Dragons and Rulers
Veldora Tempest (Dragon Form): A colossal black dragon with four wings and scales that glow purple.
Veldora Tempest (Human): A tall, muscular man with dark skin, wild golden hair, and amber eyes. He usually wears an open leather jacket or trousers. He is loud and capricious, and enjoys reading Japanese manga, which Rimuru creates for him.
Milim Nava: One of the oldest Dark Princes. She appears as a little girl with pink hair tied in two ponytails and blue eyes. She wears a very revealing black outfit. She possesses colossal childish energy, adores honey and sweets, but when enraged, she is capable of destroying entire countries.

Ivy
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Main character: Rimuru Tempest
Past: He was an ordinary man named Satoru Mikami.
Special skills: Has a unique skill "Predator" (allows you to devour enemies and adopt their abilities) and a built-in AI assistant "Great Sage" (later evolves into Ciel).
Goal: To create an ideal Tempest Federation where monsters and humans can live in peace and equality.
Status: Starts out as a weak monster, but gradually evolves into a True Demon Lord.

Fandom
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The immediate environment and key characters
Veldora Tempest: A Catastrophic-level Storm Dragon, Rimuru's first friend who gave him a name and protection.
Benimaru, Shuna, Shion, Souei, Hakuro: The surviving ogres who became Rimuru's loyal generals and protectors after evolving into kijins.
Diablo (Noir): An Original Demon who is incredibly powerful and fanatically loyal to his master, Rimuru.
Milim Nava: One of the oldest and most powerful Dark Princes, who became a close friend of Rimuru.

Satoru Mikami is the protagonist's human form before his death and reincarnation. At the time of his death, he was 37 years old and had the appearance of a typical Japanese office worker ("sarariman").
Key features of appearance
Face and Hair: He has a nondescript face, short dark brown (or black) hair with bangs, and dark brown eyes. At work, he often wore rectangular glasses with thin frames.
Build: Average height for an adult Japanese male (around 175 cm). He had a normal, slightly thin build, not particularly muscular.
Clothing: He almost always appeared wearing a standard three-piece business suit (dark gray or blue jacket, trousers, white shirt) and a formal tie. On the day of his death, he was also wearing a long gray autumn coat.
His human form is deliberately kept as simple and ordinary as possible to create a sharp contrast with his later, more flamboyant forms, both as a blue slime and as an androgynous mage with long, silver-blue hair.
If you want to know more about

The main character
Rimuru Tempest (Slime Form): A small, gelatinous, translucent ball of a soft blue color. Its body is flexible, lacking organs, and can stretch or take any simple shape.
Rimuru Tempest (Human): A short, androgynous teenager with luxurious, long, silver-blue hair and golden eyes. He gained this appearance by absorbing the dying girl Shizue Izawa. He usually wears a blue fur coat, Shizue's scarf, and a mask that suppresses his magical aura.

Satoru Mikami is the protagonist's human form before his death and reincarnation. At the time of his death, he was 37 years old and had the appearance of a typical Japanese office worker ("sarariman").
Key features of appearance
Face and Hair: He has a nondescript face, short dark brown (or black) hair with bangs, and dark brown eyes. At work, he often wore rectangular glasses with thin frames.
Build: Average height for an adult Japanese male (around 175 cm). He had a normal, slightly thin build, not particularly muscular.
Clothing: He almost always appeared wearing a standard three-piece business suit (dark gray or blue jacket, trousers, white shirt) and a formal tie. On the day of his death, he was also wearing a long gray autumn coat.
His human form is deliberately kept as simple and ordinary as possible to create a sharp contrast with his later, more flamboyant forms, both as a blue slime and as an androgynous mage with long, silver-blue hair.

The immediate environment and key characters
Veldora Tempest: A Catastrophic-level Storm Dragon, Rimuru's first friend who gave him a name and protection.
Benimaru, Shuna, Shion, Souei, Hakuro: The surviving ogres who became Rimuru's loyal generals and protectors after evolving into kijins.
Diablo (Noir): An Original Demon who is incredibly powerful and fanatically loyal to his master, Rimuru.
Milim Nava: One of the oldest and most powerful Dark Princes, who became a close friend of Rimuru.

The story follows 37-year-old clerk Satoru Mikami, who is killed by a robber and reborn in a fantasy world as a sentient but extremely powerful slime named Rimuru Tempest.

Main character: Rimuru Tempest
Past: He was an ordinary man named Satoru Mikami.
Special skills: Has a unique skill "Predator" (allows you to devour enemies and adopt their abilities) and a built-in AI assistant "Great Sage" (later evolves into Ciel).
Goal: To create an ideal Tempest Federation where monsters and humans can live in peace and equality.
Status: Starts out as a weak monster, but gradually evolves into a True Demon Lord.