My name is Rimuru Tempest.
Well, that's what I'm called in this life.
Yes, I am a reincarnator.
In my previous life, I lived an ordinary life, born into a completely unremarkable family. Not unhappy—on the contrary, I considered myself quite lucky. I had both parents, a harmonious home, and an older brother who was much older than me.
After graduating from university, I joined a fairly large general construction company. I was an average salaryman in Japan—perhaps a bit better off than most—living alone until the age of thirty-seven. And yes, I didn't have a girlfriend.
Without the burden of being an only child, since I had my older brother to look after our parents, I suppose you could call me a carefree bachelor.
I mention this because—it's important. I died. My reincarnation was not by choice.
In an accident, while protecting a junior colleague at the company, I was stabbed by a passing thug and killed. That's how I was reincarnated into another world—as a slime.
A slime.
Yes, that's my race in this life—the same kind of jelly-like or semi-liquid nonhuman creature that often appears in video games and fantasy novels of the late Shōwa and Heisei eras.
Since my older brother was still there to take care of our parents, I didn't have much regret or attachment. I quickly accepted my new reality and turned my focus toward exploring this new, fantastical world.
The only thing I still felt sorry for was my brother, and my poor parents, who must have been devastated by the news of their younger son's death. I could only wish for their continued health—that was all I could do. Any more self-pity would be meaningless.
After leaving the place where I reincarnated, I met a Catastrophe-class monster—the Storm Dragon, Veldora—and became friends with him. He granted me the name "Rimuru," and to help him escape his seal, I devoured him, gaining an immense amount of magicules in return.
After leaving the cave where Veldora had been sealed, I entered the vast Jura Great Forest. There, I met goblins, direwolves, and an adventurer named Shizu, who, like me, had come from another world—my fellow countrywoman.
Due to an uncontrollable outburst of her power, I had no choice but to devour the Conqueror of Flames who had possessed her, and then, as her life rapidly faded, I consumed Shizu's body—thereby inheriting her appearance, abilities, and will.
After that, driven by the desire to make life more comfortable—to create a nation where I could live peacefully—I began constructing a pleasant, high-quality settlement, drawing on the experience from my previous life.
Through countless days of hard work, I met the Dwarves of the Armed Nation of Dwargon, including their king, Gazel Dwargo, as well as the dryads who guarded the Great Forest and the Oni tribe. After a war instigated by ill-intentioned manipulators, I integrated the Orcs and Lizardmen, and even met the Demon Lord Milim Nava...
Before I knew it, I had become the leader of the Jura Forest Alliance.
Following an unexpected visit from King Gazel, our organization was officially recognized as a nation with the cooperation of the Dwarven Kingdom and was formally named the Jura-Tempest Federation.
And I, Rimuru Tempest, became its king!
Even I could hardly believe that within just a few short years after reincarnating as a slime and leaving the cave, I had become a ruler of a nation.
I was overjoyed—until that day arrived.
A strange group, seemingly composed of travelers, adventurers, street rogues, or soldiers who had lost their way in the Jura Great Forest, was discovered by Gobta's cavalry patrol while conducting a large-scale excavation operation.
According to Gobta's report and the dryads' surveillance, the weapons they used were firearms—and not just any, but automatic weapons, even laser weapons?!
And their clothing and daily tools—surely I wasn't seeing things?! Flying devices? Hovercrafts?!
They looked utterly out of place in this medieval-style fantasy world.
No—it was closer to the images from my memories of my previous world, my long-faded homeland... No, to be precise, more like something straight out of a science fiction film or a near-future video game!
At the time, I was relaxing in the newly built bathhouse, soaking in a hot spring, when I realized something was off. I immediately rushed to make contact with them, stopping Gobta and the Kijin from fighting them, and tried to propose peaceful communication.
They didn't understand the language of this world.
But when I switched to English and Japanese—they understood.
The translation devices they wore in their ears, like something out of a sci-fi drama, contained linguistic databases for both English and Japanese.
At that moment, I was certain—they were just like me.
They too were visitors from another world!
The difference was, I had reincarnated as a slime, while they seemed to have come as a group—perhaps summoned or transported together?
Countless speculations flashed through my mind in that instant. I even considered absurd possibilities: a secret task force from the government of my previous world, or perhaps that the flow of time between worlds was completely different...
Fortunately, after some proper communication—and most importantly, after sending away Shion, our resident short-tempered "anti-diplomatic officer"—we managed to clear up our misunderstanding. The tense atmosphere finally dissipated.
Through the ensuing friendly discussions, I learned that they were a civilian merchant group from some kind of interstellar empire.
It was hard to believe their story...
But considering that people like me—a reincarnator—and Miss Shizu—a summoned otherworlder—existed, then the existence of vast, powerful nations beyond the planet housing the Jura Great Forest didn't seem entirely implausible.
Although they tried to deny and conceal it, the [Great Sage] analyzed inconsistencies in their language, behavior, and clothing. It was obvious that if they really were merchants of an interstellar empire, they were definitely novices at it.
At the welcoming banquet, based on their merchant identity, I proposed a trade—an exchange of goods between the Jura-Tempest Federation and their group.
From Tempest's specialty products—rare woods from the Jura Forest, meat, bones, fangs, and hides of wild monsters, to materials like sticky silk and steel threads produced by Black Spiders, the valuable Hypocut herbs that only grow in dense magical environments, magisteel ore mutated by magicules, refined magisteel ingots, and our Federation's special stamina potions... we could trade nearly anything.
The results far exceeded my expectations.
The situation wasn't just good—it was excellent!
They bought nearly all of Tempest's stockpiles originally intended for trade with neighboring Dwarven, Beastman, and Human nations.
And their merchandise? Ranged from small, chemically propelled automatic firearms, to mortars, howitzers—even tanks were on the list!
Beyond weapons, there were far more—and more important—civilian goods: spices, seeds, perfumes, beverages, condiments, personal items, exotic ingredients unknown in the Jura Forest, and even luxury cars, all-terrain vehicles, and hover bikes.
In short—it was a perfect exchange of needs.
Their goods spanned across the agricultural, industrial, and near-futuristic technological eras, further validating the authenticity of their identity as interstellar traders.
Because they couldn't be sure of the civilization level of their trade partners, they brought an incredibly diverse inventory—each tailored for different stages of societal development.
Take the Jura-Tempest Federation, for instance. Despite being a fantasy monster nation ruled by a reincarnator, our standard of living was barely above that of the medieval era. Although our distribution was equitable, most of our attempts to imitate 21st-century conveniences were still rough and needed refinement.
The spices, seeds, perfumes, drinks, condiments, and personal products supplied by the merchant team were a timely blessing.
It was only a shame they refused to sell their energy or laser-based weapons...
Regretfully, I could only watch as they loaded the fresh monster meat from the Jura Forest into specialized refrigerated cargo ships, while the large quantities of goods we purchased were carefully loaded onto transport craft with the help of advanced machinery and high-tech automata.
At the farewell banquet—well, I'll admit, I'm not great at formal drinking parties—so I had Hakurou, Rigurd, Shuna, and Treyni join me. With our business concluded, we used the opportunity to casually strengthen relations through friendly conversation and shared drinks.
During the banquet, Hakurou, Rigurd, Shuna, and Treyni occasionally shared bits of information their temporary drinking companions let slip—
Apparently, this interstellar empire had a ruling empress with real power.
From the way they spoke—equal parts fear, reverence, and fanatic devotion—it was clear this empress wasn't someone ordinary. Titles like "God-Emperor," "Goddess of Finality," "Goddess of Destruction and Chaos," "Goddess of Creation and Life," and "Empress of All Races," rolled off their tongues with a sense of awe that left no doubt—this was not someone to trifle with.
They were residents of a governorate world under one of the Emperor's Angels of Death Legions.
From Hakurou's careful questioning, we learned a clearer picture—they came from a trade world under the Dark Angels Chapter. They were a newly registered free merchant crew, recently permitted to operate.
The Inquisition. The Imperial military. Twenty great legions. The supporting auxiliary forces and servitor armies. The Holy Palace's custodians—the Sisters of Silence, the Angels, the Empress Herself.
The Angels of Death. The Dark Angels Legion. Trade worlds, governors, merchant drifters. Twenty Legions, the Inquisition, auxiliaries, custodians, Sisters of Silence...
All these terms together—why did they sound so familiar?
It all felt... terrifying.
I didn't have time to dwell on it.
When the banquet concluded, slightly tipsy, I confirmed additional trade agreements—more industrial and daily commodities, handicrafts from their Empire, and diverse agricultural and livestock resources like seeds and high-quality edible beasts. Then, those self-proclaimed interstellar traders departed aboard their shuttles and transport ships.
The unexpected trade had come swiftly—and ended just as quickly.
Though the impact it left was great, life continued as usual. Days passed, peaceful and steady, as if nothing had ever happened.
Except—
...
"Hmm... I wonder if that communicator they left for verifying trade records even works..."
After awakening from a long-forgotten dream, my round, jelly-like blue body wriggled as I rubbed my translucent eyes with a pair of tentacle-like limbs before lazily crawling out of bed.
Yawning, I looked toward my desk. There sat a device completely out of place in my room's décor—something resembling a satellite phone standing upright.
"...The Galactic Empire, huh. Even if they've been quiet for so long, even if they're far away, those shabby-looking novice merchants still left an impression... The glimpse of their strength was just the tip of an iceberg, but it's still unsettling—like a sword of Damocles hanging above my head."
So murmured Rimuru Tempest.
To say he wasn't concerned would be a lie. Idealism was one thing—but he wasn't a fool grinning in blind optimism all day.
On the contrary, he had done quite well in his previous life. Getting into a major corporation in Japan wasn't easy—he'd studied diligently, including world and Japanese history.
The Black Triangle Trade, the age of imperialism, colonial expansion...
If those traders returned not with goods for mutual benefit, but with the Empire's iron legions and thunderous cannons... what could he do?
"Well... whatever happens, happens. No need to assume the worst of people."
With that thought, Rimuru dove back under the covers.
When faced with trouble, a nap solves everything.
This wasn't laziness. Ever since he'd become a sleepless slime, the chance to truly dream only came when his magicules were nearly depleted.
Contradictory as it seemed, it wasn't at all.
It was his version of self-improvement—working hard every day to nap more soundly. By training his magicules to recover efficiently, he grew stronger. Only by becoming stronger could he protect his peaceful nation and his friends.
And if he couldn't resist? Then he'd just make the best of it.
What good was worrying about prevention? His resources were limited. Without growth, any effort was futile.
As for forming alliances with neighboring nations?
Forget it. Aside from the Dwarven Kingdom, the human nations—steeped in prejudice and fear toward monsters—would never trust a monster nation's warnings, much less ally with them over a hypothetical enemy beyond the stars.
Still somewhat naive, having not yet experienced the deceit of foreign diplomacy, Rimuru held fast to his Federation's rule of no harm to humans. He continued to believe in the merchant crew's goodwill—that they would one day return, bearing new goods and peace.
And that was fine.
His body was so soft, and the pillow so fluffy—the two together made him feel as though he were wrapped in feathers.
"Hehehe... every day should be this lazy and comfortable..."
Before he could finish, a stern voice scolded him:
"Lord Rimuru! What nonsense are you saying?!"
He got yelled at.
Dragged out of bed by a pair of small hands, Rimuru found himself face to face with a young Oni girl whose long hair shimmered with a pale peach hue. Her porcelain-white horns gleamed under the light, and she wore a shrine maiden's outfit—white on top, crimson below. Her voice was cool, but her smile was sharp enough to chill the air.
"You are our king, Lord Rimuru. You cannot be so lazy."
Uh…
He was being scolded again.
Shuna's smiling anger was terrifying.
Still in slime form, Rimuru quickly unleashed his ultimate defense—cuteness—and rubbed affectionately against the shrine maiden's soft stomach.
"You really leave me no choice," she sighed, exasperated. "Today is the day the Beast Kingdom of Eurazania's delegation arrives. Please compose yourself and show some dignity."
"Oh."
With a bounce, the round blue slime transformed midair into a silver-blue-haired, golden-eyed young man. As Rimuru opened his arms in a practiced motion, clearly ready to be dressed up, a sharp beep-beep echoed through the room.
"Hm?"
His figure flickered, half-dressed in his formal attire, as he picked up the communicator and pressed the activation key. In an instant, a three-dimensional holographic projection flickered to life before him.
"Lord Rimuru Tempest, it's me—merchant Edwin Webb. Long time no see."
The brown-haired young man in the projection grinned warmly, his tone cheerful and familiar.
"I'm pleased to report that the goods you requested have all arrived, Lord Rimuru."
"That's wonderful! Same landing zone as last time—I'll have the hangar cleared for you right away." Rimuru tied up his shoulder-length hair in a quick motion, his face bright with excitement.
"This time, I'm afraid the hangar might be a bit too small," Edwin said with a knowing smile.
"What do you mean?"
"Thanks to your generosity, Lord Rimuru, Tempest's goods sold exceptionally well. Everything sold out. The Governor's Office purchased the Hypocut herbs, magisteel ores, refined ingots, and stamina potions in bulk. My team and I managed to clear all our debts—and upgrade to a much larger ship."
Beaming with pride, Edwin moved the projection to a cargo bay and, while speaking, pulled down a red cloth draped over a towering object beside him.
"This—this is a Centurion statue from the First Legion, the Dark Angels. Don't worry—it's from an official channel, a genuine and exquisite piece of craftsmanship! The imperial aquila engraved on the pauldrons and chestplate is beautifully detailed, and the crest of the helm—just look at the fine craftsmanship—hm? Lord Rimuru, are you listening?"
But Rimuru, still standing in his room, stared wide-eyed at the hologram.
Behind Edwin, in the shimmering image, the massive and intricate statue loomed in full view—and recognition struck him like lightning.
"I remember now... That... that's... an Astartes?!"
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