To Restore my Family Honor, I Enlist as a Steam Samurai of Jōkipon.

This short story serves as a prologue to the world of Jōkipon, introducing the setting through the eyes of a rookie courier named Tenshi.

I hope you'll enjoy experiencing the everyday life, culture, and people of Jōkipon through his very first run.

The main story follows a different protagonist—a young woman who sets out to become a steam samurai in order to restore her family's honor.

I hope this short story serves as your gateway into the world of Jōkipon.

---

Kinetic Core, Activate, Off to Jōkipon.

The steam relay station smelled of warm brass and pressurized steam.

Steady pulses of warm air surged through the vents, as if the station were breathing. Hissing quietly, copper pipes went along each wall. The gauges were ticking. The cylinders turned. Everyone inside the building moved in a measured, purposeful, and effective manner because the building as a whole was driven by pressure and rhythm.

Tenshi did not feel measured or deliberate.

He stood at the assignment counter with both hands at his sides, trying to look like someone who belonged here. He was seventeen, one week into his courier posting, and this was his first solo run.

Senior Courier Shota set the message cylinder on the counter between them.

It was smaller than Tenshi expected. Lacquered black, sealed at both ends with the Imperial chrysanthemum stamp in red wax. No markings indicating origin. No markings indicating destination. Just the seal and the weight of it.

"New couriers are always given running jobs," Shota said. He was a compact man in his forties with forearms like rope and a voice that carried no particular emotion. "Before you earn a sky route, you learn the streets. Before you learn the streets, you learn the rooftops."

"Yes, sir."

"The barracks on Pressure Hill. Third division relay point. You know it?"

"I studied the city map."

Shota looked at him the way experienced men look at young ones who have studied maps. "Good. Then you won't get lost."

He slid the cylinder across the counter. Tenshi took it with both hands, checked the seal, both ends intact, wax uncracked, and fastened it to the carry loop at his waist. He felt it settle against his hip. Light. Whatever was inside weighed almost nothing.

He wondered what it was.

He didn't ask.

Shota moved to the equipment rack along the back wall. Rows of kinetic cores hung in their charging cradles, flywheels dormant inside their housings, each one connected to the station's geothermal feed by thin copper lines. Shota selected one without hesitation, middle row, third from the left; disconnected it from its cradle; and carried it to Tenshi.

"Turn around."

Tenshi turned. He felt the core settle onto his back, felt the mounting brackets lock into the receiver plates on his courier vest with a solid click-click-click. Then Shota's hands moved efficiently across the connection points, tightening, checking, tightening again.

“The activation switch is on your left shoulder strap," Shota said. "You know how it works?"

"Flywheel stores kinetic energy. The core charges from movement and impact and releases it through the leg and arm channels on demand. The more momentum I build, the more I have to spend."

"And if you spend it all at once?"

"The core goes cold. I run on my own legs until it recovers."

"How long does recovery take?"

"Depends on movement. Ten minutes of normal running. Less if I take impact."

Shota came around to face him. He looked at Tenshi for a moment with the same neutral expression, then reached out and tapped the cylinder at his hip.

"Don't break that."

"Yes, sir."

"The seal matters more than the contents. Arrive with a broken seal, and it's the same as not arriving." He paused. "Worse, actually."

Tenshi nodded.

Shota stepped back and said nothing further. The dismissal was in his posture.

Tenshi reached up, found the activation switch on his left shoulder strap, and pressed it.

The core hummed.

Deep and low at first, almost below hearing. Then it climbed in pitch as the flywheel began to spin, slow rotations accelerating, the gyroscopic weight of it finding its axis. He felt it in his spine first. Then his shoulders. Then a strange, spreading lightness moved down through his hips and into his legs, as though the gravity pressing him into the floor had simply decided to ease its grip.

His armor felt like nothing.

He lifted one foot experimentally. Set it down. The motion felt effortless in a way that was almost disorienting.

He looked at Shota.

Shota looked back at him.

"The gate's waiting," the senior courier said.

Tenshi ran.

He didn't just jump; he detonated the pressure valves. As his boot struck the edge of the clay tiles, the Gen 3 Core behind him screamed at twenty-eight thousand revolutions per minute. Internal gears groaned. The control rotor tilted against the sea wind. Steam erupted from the ankle vents.

PSSSHHH.

The rooftop vanished beneath him.

***

Today is my first day as a courier.

The senior says every new courier gets a running job. Personally, I think they just enjoy watching us fall off rooftops.

I laughed.

Excitement replaced my nervousness.

I leaped again.

And again.

The rooftop vanished beneath me.

Wind rushed past my ears. Steam hisses from my ankles with every leap, every vault, every impossible landing that should have shattered my legs but instead launches me skyward again.

I was flying.

The rooftops of Jōkipon spread before me like a copper sea. Clay tiles gleam in the afternoon sun. Smokestacks exhale white plumes. Somewhere below, the city hums with a million lives I can't see.

I jump. Land. Jump again.

This is what I was born to do.

While crossing the market district, I slowed on a low rooftop. A crowd of children had gathered below, spinning miniature kinetic tops that hummed and hovered just above the ground. The one that flew highest won.

I slow down.

A loose tile caused my foot to slip.

The city tilted.

For a moment I thought I was going over the edge.

Then the core hummed.

The control rotor whined.

My body jerked upright.

I stumbled twice before catching my balance.

So that's what the third wheel was for.

I steadied myself and dropped down into the square.

One of the boys looked up, eyes wide.

“Would you like to play too, Courier-san?”

He held out his top with both small hands. I crouched and accepted it…

---***---

…when his rough fingers brushed mine, everything felt warmer.

The courier’s hands were calloused and strong, like he’d been running for hours, but his grip was gentle when he took my top. Steam wisped from his shoulders. His core hummed steadily beneath the armor. He looked just like the heroes from Grandmother’s nighttime stories: tall, steady, and carrying secret messages across the whole city.

I smiled up at him.

They carry messages across the whole nation. They see the Steam Torii. They run along the coast. They know what lies beyond the Great Gate.

I would like to run across the rooftops one day as well.

I want to feel the breeze on my face. I want to hear steam hissing from my own ankles.

I hope Tenshi's first delivery goes well.

He spun my top. It wobbled almost right away. I laughed, and the other children burst into giggles with me.

A girl stepped forward next. Her top spun perfectly, rising higher than anyone else’s.

“You lost again!” everyone cheered.

The children erupt in joy.

He was easily defeated by a young girl.

"That's Hinata, and she's fantastic at this top game. She's always improving her top.”

"She'll be an engineer," they said. "Or something even greater."

The courier rubbed the back of his neck, steam hissing softly from his ankle vents.

The children giggled. Hinata's grin widened.

"You're better at this than I am,” he said, handing the top back to me with a sheepish grin…

---***---

…He took it from my hand. Embarrassed, steam hisses from my ankles as I launch back onto the rooftops.

I straightened, the laughter of the children still ringing behind me. The cylinder at my hip was a quiet weight, reminding me I still had a delivery to finish. I gave them one last nod, then triggered the pressure valves.

Steam hissed. The rooftops called.

I launched upward, the core singing against my spine as I leapt back into the rhythm of the city.

Continuing my route to the Steam Samurai headquarters.

Another courier streaks past me so quickly we only exchange a nod.

A blur of steam and motion. A flash of iron-gray armor. Then gone.

I don't catch his face. I don't catch his name.

But I catch his pace.

He’s faster than me. More experienced. His core hums with a sharper note, a higher pitch that speaks of years of service.

I watch them disappear across the rooftops.

Someday, I think.

Someday, that'll be me.

The building looms above the surrounding district, a fortress of iron and stone, with steam pipes snaking across its exterior like metal veins. Pressure vents line the walls, releasing rhythmic bursts of vapor into the afternoon air.

I slow my pace.

Through the open training yard gates,

I arrive at the military barracks.

I had just handed the sealed cylinder to the relay officer at the barracks when I heard it.

CLANG.

The sharp ring of steel echoed from the open training yard. Then another.

CLANG.

Followed by the familiar hiss of pressurized steam.

My feet stopped before my mind gave the order. Curiosity pulled harder than duty. I glanced around once, then slipped toward the arched gateway leading into the training yard instead of heading straight back to the rooftops.

The yard was wide and paved with reinforced clay tiles, scarred from countless impacts. At its center, two Steam Samurai were locked in a mock duel.

They moved like living machines.

Both wore full kinetic battle armor, layered plates of blackened steel and brass etched with imperial crests. Thick hoses and copper tubing ran along their limbs, feeding power from the humming cores mounted on their backs. With every powerful step, steam vented from ankle and shoulder exhausts in sharp, controlled bursts.

The taller samurai lunged, katana whistling through the air. His opponent parried with a ringing clash. The impact sent sparks flying, and both warriors’ gauntlets released synchronized jets of steam to absorb the recoil. The shorter one twisted, using the momentum to spin into a low-sweeping kick. His opponent leaped over it, the gyroscopic stabilizers in his core whining as he twisted in mid-air and came down with an overhead strike.

CLANG!

Pressure valves screamed. Steam billowed across the yard in white clouds. The ground trembled slightly under the force of their movements. These weren’t ordinary soldiers; they were extensions of the machine. Every strike, every dodge, every burst of steam was calculated power.

I couldn’t look away.

The way they fought was beautiful. Brutal, yes, but also precise and rhythmic, like a deadly dance powered by the heartbeat of the earth itself. One samurai’s core glowed faintly orange from sustained use, while the other’s vented excess pressure in sharp “pshhh” bursts with every leap. Their helmets, shaped like snarling guardian spirits, reflected the afternoon sun off polished brass visors.

For a moment I forgot to breathe. My own core hummed quietly against my back, suddenly feeling small and simple compared to the monsters they wore. This was what I could become one day. Not just a courier leaping across rooftops, but a warrior who could move like living steam and steel.

I must have stepped closer without realizing it.

A deep voice cut through the sound of battle.

“Back to work, courier.”

An instructor, an older samurai with gray at his temples and a core twice the size of mine, stood at the edge of the yard, arms crossed. His gaze was stern but not unkind.

I straightened immediately, cheeks burning. “Yes, sir!”

I bowed quickly and hurried away, boots clattering on the tiles. But even as I scaled the outer wall and launched back onto the rooftops, the image stayed burned into my mind: the flash of katanas, the rhythmic hiss of steam, the raw power of the Steam Samurai.

I hurry away.

I pass a row of workshops where mechanics are hanging from pressure pipes, repairing leaks.

They dangle from safety harnesses, tools strapped to their belts, wrenches in hand. Steam hisses from the cracks they're sealing. Brass fittings glint in the afternoon light.

One of them notices me. He gives a lazy salute with his wrench.

I nod back.

Below them, steam pools across the cobblestones. The air smells of hot metal and oil.

These are the ones who keep the city running, I realize. Without them, the cores would fail. The pressure mains would burst. The couriers would stop.

I run a little faster, grateful for their work.

I climb a communications pole overlooking the city.

I balance at the top. The wind pulls at my clothes.

I remove a Steam communicator. Pressure needles move across a brass gauge.

I report successful delivery.

Headquarters acknowledges receipt.

My first mission is complete.

With time remaining before I had to return to the relay station, I turned my steps toward the coast. The core’s hum had settled into a comfortable rhythm against my back as my route led me through the long valley lined with ancient Steam Torii.

The gates rose one after another, towering vermilion arches carved from stone and reinforced with brass and copper. Geothermal steam flowed steadily through channels cut into their pillars, whistling softly as it escaped through carefully placed vents. Each torii seemed to breathe. Warm, mineral-scented mist curled around the crossbeams like living silk, catching the afternoon light and turning it pale gold.

I slowed to a walk along the ridge path, letting the core spin down. Travelers below moved in quiet procession. Some bowed deeply as they passed beneath the arches. Others simply paused, eyes closed, letting the warm steam brush their faces. No one fully understood why the ancient builders had designed them this way; some said the gates honored forgotten gods, and others claimed they channeled the living pulse of the earth itself.

The truth had died with the builders long ago, leaving only rhythm and reverence.

I found a smooth outcrop and crouched there, watching. One torii stood taller than the rest, its apex crowned with a spinning kinetic vane that turned endlessly in the rising steam. The sound it made was almost musical—like a low, constant note played on a giant flute. I closed my eyes and let the warm air wash over me. For a moment the weight of the sealed cylinder at my hip, the pressure of my first solo run, and the endless rooftops all felt distant.

What would it be like, I wondered, to run through a land filled with these gates? To feel steam rising beneath my boots on every road, every mountain pass?

A soft chime sounded from the nearest torii as a group of monks in oilskin robes passed beneath it. Their kinetic lanterns bobbed gently at their sides, glowing soft amber. One of the older monks glanced up toward my ridge and offered a small, knowing nod, as if he could see the question written across my face.

I returned the bow from where I sat.

Just in case.

Eventually I rose, the core already waking again with my movement. I followed the valley path until the land opened up and the enormous outer wall of Jōkipon came into view, cutting across the horizon like the edge of the world itself.

Soldiers were preparing for patrol along the battlements. I watched them strap on their own kinetic cores, check pressure gauges, and test the hiss of steam from their gauntlets. They moved with the easy confidence of men who had done this for years. None of them looked afraid of what lay beyond the wall. Only… curious.

I climbed the access stairs and stepped onto the wall at sunset. The Great Gate stretched beneath me—massive, ancient, and firmly closed. Beyond it, the unknown unfolded in layers of shadowed mountains, distant glittering seas, and fading golden light. Cities I had only heard of in stories. Roads I had never run. Torii whose steam I had never tasted.

I stood there for a long time, wind tugging at my courier vest, the cylinder warm against my hip.

I smiled.

“Tomorrow,” I whispered to the horizon, “I’ll run even farther.”