The Yandere villainess loves the useless engineer

The steam car finally died with a loud hiss as I brought it to a stop outside the shack.

The engine clicked softly while excess steam escaped through the pressure valves into the cold evening air. Even after hours of testing, I still occasionally caught myself staring at the machine in disbelief.

It worked.

Poorly.

Violently.

Dangerously.

But it worked.

Finn climbed out stiffly from the passenger side before immediately stretching his back.

"I think my spine shattered three separate times during that ride."

"That means the suspension needs improving."

"That means roads shouldn’t look like they were designed by drunk goats."

I smirked slightly before stepping down from the vehicle carefully. My prosthetic leg hit the dirt with a dull wooden knock while I looked back over the machine again.

The boiler still radiated heat.

The flywheel spun slower and slower until finally stopping entirely.

Even now I could already see improvements forming in my head.

Better pressure regulation.

Lighter frame construction.

Proper rubber tires eventually.

Improved braking.

More efficient pistons.

Higher pressure boilers.

The possibilities kept expanding endlessly.

Finn noticed the look immediately.

"...You’re doing the thing again."

"What thing?"

"The terrifying inventor stare."

"I don’t have a terrifying stare."

"You look like you’re about to industrialize human suffering."

I ignored him.

After securing the vehicle inside the workshop and covering the more sensitive components, the two of us finally split for the evening.

Finn remained at the shack while I headed back toward the manor through the forest roads.

The walk felt strangely calm.

No purple-haired menace suddenly appearing beside me.

No threats about eternal love.

No one staring at me while I slept.

The silence honestly felt unsettling now.

That realization disturbed me deeply.

By the time I reached the manor, the sky had already darkened completely while warm lights glowed from the windows.

The moment I stepped inside, my mother immediately noticed me.

"Leon."

She walked over quickly before pausing slightly.

"...Why do you smell like smoke and hot metal again?"

"The usual reasons."

"That answer worries me more every time."

She sighed softly before holding out an envelope toward me.

"You received a letter from the kingdom."

I blinked.

"A letter?"

The envelope itself immediately caught my attention.

Dark wax.

Royal insignia.

Official.

I carefully took it before breaking the seal open.

My mother watched curiously while I unfolded the paper.

At first my expression remained neutral.

Then slowly—

"...What?"

"What is it?"

I stared at the letter again just to make sure I actually read it properly.

Then finally read part of it aloud.

"’In recognition of extraordinary achievements in aiding the defense of the border during impossible circumstances...’"

My mother’s eyes widened slightly.

I continued reading.

"’The Kingdom of Valenor hereby grants Leon Aldric stewardship over the territory of Blackwater Hollow and all associated lands and villages therein.’"

Silence filled the room.

My mother blinked several times.

"...They gave you land?"

"...Apparently."

Then slowly—

"...I have territory now."

My mother suddenly smiled brightly before immediately pulling me into a hug.

"Leon!"

"I can’t breathe."

"I’m proud of you!"

I awkwardly stood there while she held onto me tightly.

It still felt absurd.

Nobles receiving territory wasn’t unusual.

But I was young.

Very young.

And despite helping defend the border, I still never expected the kingdom itself to directly reward me.

Especially not with land ownership.

After finally escaping my mother’s hug, I looked back down at the letter again more carefully.

Most of it covered formalities.

Titles.

Recognition.

Legal confirmation.

Tax structures.

Then my eyes moved toward the actual details regarding the territory itself.

"...Huh."

"What?"

I frowned slightly while reading further.

"It’s small."

"How small?"

"Two villages apparently."

I continued reading.

"Mostly forests... some farmland... low population..."

Then suddenly I paused.

"...Wait."

My mother tilted her head slightly.

"What is it?"

I looked down at the location again.

Blackwater Hollow.

My expression slowly became more suspicious the longer I stared at it.

"...No way."

"What?"

I looked up slowly.

"It’s near the Nightbane Duchy."

My mother blinked.

"Near it?"

"No."

I reread the line again carefully.

"Inside it."

"...What?"

"The territory is completely surrounded by Nightbane-controlled lands."

Now even my mother looked confused.

"That seems strange."

I nodded slowly.

Very strange.

The Nightbane Duchy controlled enormous stretches of territory surrounding their capital. Any land enclosed inside those borders held massive strategic importance and furthermore it was practically beside the capital itself.

Which meant one thing.

This territory absolutely should not have gone to some random young noble from the Aldric family.

Unless—

My eyes narrowed slightly.

"...Lillith."

My mother looked surprised.

"You think she had something to do with it?"

"She left one day ago."

"And?"

I slowly lowered the letter.

"...You say that like she’s normal."

Silence.

Then my mother sighed.

"...Fair point."

The more I thought about it, the more suspicious it became.

The location alone made no sense politically.

Giving territory directly beside the Nightbane capital to another noble family should have created complications immediately.

Unless Duke Rosthwall personally approved it.

Which meant either Lillith begged her father, threatened her father, manipulated the royal court, or some horrifying combination of all three.

Honestly, I wasn’t sure which possibility scared me more.

My mother sat beside me afterward while smiling softly.

"Still."

She gently patted my shoulder.

"You should be proud of yourself."

I looked down toward the letter silently.

Proud.

It still felt strange hearing that.

A few months ago I was hiding in a shack while experimenting with primitive rifles.

Now I owned land.

Built steelworks.

Created a steam engine.

And accidentally started changing warfare.

The pace my life had escalated at honestly felt unreasonable.

My mother eventually stood again.

"You should get some rest."

I nodded slightly.

"...Yeah."

After folding the letter carefully, I headed upstairs toward my room.

The manor felt unusually quiet tonight.

Mostly because Lillith wasn’t there.

No destroyed doors.

No glowing purple eyes in the darkness.

No girl silently sitting beside my bed staring at me for hours.

I stopped briefly after entering my room.

Then instinctively looked toward the chair near the corner.

Empty.

"...That’s still creepy."

I sighed before sitting down on the edge of the bed.

Then looked toward the letter one final time.

Blackwater Hollow.

A small territory near the Nightbane capital surrounded entirely by Nightbane lands.

I already knew this was not a coincidence.

Which meant eventually—

I would probably have to visit it.

And somehow that thought alone made me nervous.

The next morning I headed back toward the shack with the royal letter folded inside my coat pocket.

The forest path remained quiet aside from the distant sounds of axes and wagon wheels somewhere deeper inside the territory. Even though the industrial district had been built far away from the shack, its influence could still be felt everywhere throughout Aldric lands.

More roads.

More workers.

More shipments.

More smoke rising in the distance.

The territory itself slowly felt like it was changing shape around my inventions.

By the time I pushed open the shack door, Finn was already inside hammering something aggressively.

CLANG.

CLANG.

CLANG.

"...You know hitting metal harder doesn’t automatically improve it right?"

Finn looked up immediately.

"It makes me feel better."

"That explains a lot actually."

I tossed the folded letter onto the workbench.

Finn caught it curiously before opening it.

At first his expression looked uninterested.

Then confused.

Then shocked.

"...Wait."

He reread part of the letter.

"They gave you land?"

"Apparently."

Finn slowly looked back up.

"You own territory now?"

"It’s tiny."

"You’re saying that like normal people casually own villages."

I shrugged slightly before grabbing a nearby sketch.

"It’s mostly forests and two villages."

Finn looked back down at the letter.

"Blackwater Hollow..."

Then his eyes narrowed slightly.

"...Why is it inside Nightbane territory?"

"That’s the concerning part."

Finn slowly lowered the paper.

"...You think she did this?"

"She absolutely did this."

"That woman is horrifying."

"I know."

Finn stared at the letter for several more seconds before sighing.

"So when are you going to see it?"

"In a couple days."

Then I added casually:

"You’re coming with me."

Finn froze.

"...I’m sorry?"

"You heard me."

"Why."

"Because I don’t trust this."

"You don’t trust the territory?"

"I don’t trust Lillith."

Finn immediately pointed toward me.

"That is the smartest thing you’ve ever said."

I ignored him and walked toward the steam car sitting near the rear of the workshop.

Now that the machine actually functioned, its flaws had become painfully obvious.

The suspension still felt rough.

The steering fought itself occasionally.

The braking system needed improvement.

And worst of all—

Steam leaked from nearly every connection point.

I crouched beside one of the pipe joints before tightening another fitting.

A loud hiss immediately answered me.

"...I hate this."

Finn walked over beside me.

"The steam is leaking again?"

"It’s always leaking."

The problem wasn’t the metal itself.

The seals simply weren’t good enough.

Every connection point between pipes, pistons, valves, and pressure chambers slowly lost steam no matter how carefully I machined the components.

Pressure escaped.

Efficiency dropped.

Power became inconsistent.

I grabbed one of the current piston seals from the table.

Layered cloth.

Compressed fiber.

Treated leather.

Primitive garbage.

The materials dried out, warped under heat, or failed entirely after prolonged use.

I leaned back slightly while thinking.

Flexible.

Elastic.

Water resistant.

Heat resistant.

Then suddenly—

"...Rubber."

Finn blinked.

"...What."

I looked up sharply.

"Are there trees that produce latex?"

Finn somehow looked even more confused.

"...You lost me immediately."

"White sticky sap."

"Oh."

Finn crossed his arms.

"And why exactly do we need tree slime?"

I immediately started sketching rough sealing rings onto paper.

"Because if I can stabilize it properly, it could solve half the sealing problems with the engine."

Finn stared at me blankly. 𝒇𝙧𝙚𝓮𝔀𝓮𝒃𝙣𝓸𝒗𝒆𝒍.𝙘𝒐𝒎

"You looked at leaking steam and concluded we needed magical forest goo."

"It’s not magical."

"That was not the important part of the sentence."

The more I thought about it, the more useful the material became.

Pipe seals.

Pressure gaskets.

Shock dampening.

Wheel padding.

Steam insulation.

It could improve almost every issue I currently had.

Which meant there was only one person to ask.

"...We need Cedric."

Finn sighed heavily.

"I knew you were about to drag me somewhere."

A while later we arrived at the merchant district near one of the larger trade roads running through the territory.

Compared to the isolated forests surrounding the shack, the area felt crowded and noisy. Wagons rolled through muddy roads carrying military supplies, steel shipments, food crates, and charcoal deliveries.

The war had transformed trade completely.

Everything moved faster now.

Everyone smelled profit.

Near the center of the district stood one of the larger stone buildings belonging to the Valamere Trading Corporation.

Unlike most structures nearby, the building looked expensive.

Clean stone walls.

Glass windows.

Polished wood.

Private guards.

Money practically radiated from the place.

Finn glanced upward slightly.

"I still don’t trust merchants."

"You don’t trust anyone."

"That’s because people are usually terrible."

I pushed the door open.

Several employees immediately recognized me.

That still felt strange.

A few months ago I was just a noble’s son hiding in a shack experimenting with metal tubes.

Now merchants whispered about the border battle, the smoke weapons, the steelworks, and the strange machines appearing within Aldric territory.

One employee quickly disappeared upstairs.

Moments later Cedric Ross emerged from one of the offices.

The merchant representative looked exactly as polished as always.

Expensive clothing.

Perfect posture.

That same calculated smile.

"Lord Leon."

I still hated hearing that title.

Cedric extended a hand politely.

"To what do I owe the pleasure?"

Finn muttered quietly beside me.

"He definitely scams people."

Cedric smiled pleasantly.

"I appreciate honesty."

I got straight to the point.

"I need information."

Cedric’s expression sharpened slightly immediately.

"About?"

"Southern trade routes."

Now the merchant looked interested.

"That’s rather broad."

I folded my arms.

"I’m looking for trees that bleed white sticky sap."

Silence.

Cedric blinked once.

Then twice.

"...I’m sorry?"

"A white elastic substance."

Finn helpfully added:

"Tree slime."

Cedric slowly looked between the two of us.

"...May I ask why?"

"No."

I continued.

"Hotter climates. Possibly jungle regions or tropical environments."

Cedric tapped one finger lightly against the desk while thinking.

For the first time his expression became genuinely thoughtful rather than professionally polite.

"...I may have heard something similar before."

My attention sharpened immediately.

Cedric walked over toward several shelves before pulling out a trade ledger.

"Some southern merchants occasionally transport processed resin blocks harvested from certain coastal regions."

"Resin?"

"They collect it by cutting into the bark."

I stepped closer.

Cedric flipped through several pages.

"Most people consider it fairly useless. It melts under excessive heat and hardens strangely in colder climates."

Latex.

It had to be.

Cedric looked back toward me.

"...What exactly are you planning to do with it?"

"Industrial applications."

Cedric sighed softly.

"That phrase always leads to something dangerous with you."

Finn nodded immediately.

"He’s correct."

Cedric closed the ledger after several moments.

"I can send inquiries through the corporation’s southern trade routes."

"How long?"

"A few weeks for confirmation."

I frowned slightly.

Cedric noticed immediately.

"You seem unusually eager for tree sap."

"You have no idea."

The merchant gave me a long suspicious look before smiling faintly.

"...Very well."

He adjusted one of his gloves calmly.

"I’ll investigate it personally."

I nodded once.

"That’s all I needed."