Rimuru Tempest is the slime at the center of That Time I Got Reincarnated as a Slime — a former salaryman who wakes up in a monster-filled world with absurd skills, a calm problem-solver brain, and a habit of turning enemies into neighbors. This guide covers who Rimuru is, how the powers work in plain language, and where the protagonist fits without dumping every late-series twist.
Quick information
- Role: Protagonist; founder of the Jura Tempest Federation
- Also known as: Rimuru; Satoru Mikami (former human name); slime lord of Tempest
- First appearance: Season 1 Episode 1 (anime)
- Voice: Miho Okasaki (JP) · Brittney Karbowski (EN)
- Series: That Time I Got Reincarnated as a Slime
Who is Rimuru Tempest?
Rimuru starts as Satoru Mikami, an ordinary adult stabbed in Tokyo and reborn as a slime in a cave that already feels like a mid-boss dungeon. The joke of the premise is that a formless blob should be weak. The series immediately flips that: Rimuru comes with Predator (later upgraded) and Great Sage, which means the slime can analyze, absorb, and solve problems like a walking strategy guide. Personality stays human — dry humor, practical ethics, a soft spot for people who get treated as disposable.
What makes Rimuru stick as a lead is not raw overpowered fantasy alone. It is nation-building. Early on, naming goblins and direwolves is not just a power-up montage; it is Rimuru choosing to treat monsters as people with jobs, names, and futures. Tempest grows because Rimuru is weirdly good at logistics: housing, trade with dwarves, diplomacy with humans, and “please stop eating the guests” HR. If you are coming from our Episode 1 review, that cave opening is the entire thesis — reincarnation as a second chance to do life with clearer priorities.
Light spoiler territory for the path ahead: Rimuru’s story arcs toward Demon Lord territory and heavier political weight. This page stays light on late reveals. The important early identity is simpler — a slime who wants a peaceful town and keeps accidentally becoming the strongest person in the room. That tension — cozy town sim versus escalating war epic — is the franchise. Rimuru is the hinge both genres swing on.
Readers also search Rimuru because the character breaks a few isekai defaults. The slime does not spend seasons pretending to be weak for a revenge twist. Power arrives early; the drama becomes what you do with it when merchants, knights, and Demon Lords all want a piece of your forest. Rimuru’s answers are oddly civic: roads, baths, alliances, and only then annihilation. That mix is why the character still dominates discussion years after Season 1.
Personality
Rimuru talks like someone who has already sat through too many office meetings. Decisions come fast, but the tone stays easygoing until someone threatens Tempest’s people. Then the mask slips: cold calculation, absolute retaliation, zero interest in half-measures. That dual gear — chill mayor vs. terrifying predator — is the character’s real hook.
With allies, Rimuru is generous to a fault: names, food, housing, and trust handed out early. With schemers, Rimuru is transactional and sharp. The slime also has a soft, almost parental streak toward kids and underdogs, and a shameless love of hot springs, food, and human comforts. Flirtatious jokes and gender-fluid presentation in human form show up as comedy, but the core personality stays consistent: protect the town, upgrade the town, keep the chaos fun if possible.
Powers & skills
Rimuru’s kit is the reason half the internet searches this character. Here is the practical version readers actually want — what the skills do, not a wiki dump of every Unique Skill name.
Core abilities
- Predator / Gluttony line: Absorb targets, store them, analyze traits, and reuse abilities. This is the engine behind Rimuru’s growth curve.
- Great Sage (and later evolution): Instant analysis, skill optimization, and that famously dry inner monologue that keeps Rimuru from dying to dumb mistakes.
- Slime body: Near-immortal durability for early threats, shapeless movement, and later full humanoid mimicry for diplomacy and combat.
- Naming: Grants monsters evolution and loyalty; also creates political bonds that matter as much as raw stats.
Evolutions & forms
Rimuru begins as a slime, gains a humanoid form tied to a key early encounter, and later climbs into Demon Lord–adjacent territory as the story raises the stakes. Exact thresholds and titles are medium-to-heavy spoilers; what matters for new viewers is the pattern: every major crisis expands Rimuru’s toolkit and Tempest’s map at the same time.
Role in the story
Rimuru is the gravitational center of Tensura’s plot. Season 1 is largely Rimuru’s origin as a ruler: escape the cave with Veldora, build a goblin village into a nation, absorb crises with orcs, knights, and neighboring powers, and learn that peace requires strength people respect. The emotional spine early on runs through Shizue Izawa — a human connection that makes Rimuru’s goals feel personal, not just empire sim.
Later seasons push Rimuru from clever local boss into a figure who has to answer for Tempest on the world stage. Diplomacy, revenge arcs, Demon Lord politics, and alliance-building all orbit the same question: can a reincarnated softie keep a monster nation safe without becoming the monster everyone feared? For the bigger watch verdict, see our Season 1 review and overall review.
Relationships
- Veldora Tempest: Chaotic older-brother energy sealed in a cave; Rimuru’s first true friend and namesake link.
- Shizue Izawa: Human teacher whose life and will reshape Rimuru’s human form and priorities.
- Benimaru: Flame general and military backbone of Tempest.
- Shion: Loyal secretary with terrifying strength and questionable cooking.
- Souei: Shadow intelligence chief Rimuru trusts with dirty work.
- Ranga: Named direwolf partner and battle mount energy incarnate.
- Milim Nava: Demon Lord “bestie” who tests Rimuru’s patience and soft power.
- Gobta: Comic underdog who still gets trusted with real missions.
- Hakurou: Sword mentor who turns Rimuru’s chaos into technique.
Best moments
Rimuru’s best scenes are rarely just “big beam wins.” The cave conversations with Veldora set the friendship tone. Naming the goblin village lands as both power fantasy and found-family. The first serious defenses of Tempest show Rimuru’s cold side without losing the sitcom energy of town life. Shizu’s arc is the emotional peak of Season 1 for a reason — it is where the slime’s human past and monster future collide. And whenever Rimuru sits in a hot spring after a diplomatic disaster, the show reminds you this protagonist still wants a comfy second life, not endless war.
FAQ
How strong is Rimuru Tempest?
Top-tier by design. Early Rimuru already outscales most local threats through analysis and absorption; later arcs push into Demon Lord–class politics and combat. Strength is less interesting than versatility — Rimuru wins by adapting mid-fight and mid-negotiation.
When does Rimuru first appear?
From the first minutes of Season 1 Episode 1. If you want the beat-by-beat take, start with our S1E1 review.
Is Rimuru a boy or a girl?
Rimuru’s former life was male (Satoru Mikami). As a slime, gender is fluid/neutral; the humanoid form reads feminine to many characters, and the series plays that for comedy and diplomacy. Canon leans on Rimuru as Rimuru.
Should I know about Rimuru before watching?
No. Rimuru is the on-ramp. Trailers spoil scale; the show explains skills as they appear.
What is Rimuru’s goal?
A peaceful, prosperous monster nation where friends can eat well and not get hunted. Everything else — alliances, wars, Demon Lord drama — is the cost of protecting that goal.
Is Rimuru overpowered in a boring way?
Sometimes the power fantasy is cozy and stacked. What keeps it watchable is Tempest’s people, political messes, and Rimuru’s personality. If you only want underdog struggle every episode, this is not that show — and Rimuru is why.
Keep exploring
Your turn
Favorite Rimuru moment so far — cave friendship, nation founding, or a colder revenge beat? Do you prefer slime-form comedy or humanoid diplomacy Rimuru? And which Tempest subordinate should we deep-dive next?