Crossover Shipgirls: Building a Dimensional Empire from Scratch

”The tech tree went off course the moment I stepped out the door.”

This was Setsuna’s conclusion about his current situation.

With the support of the Azur Lane shipgirls, his settlement had rapidly advanced to the early space-age level—or, more accurately, its military technology had reached that level. In contrast, fields like agriculture and light industry were virtually non-existent.

This contrast became even more apparent when he reviewed the settlement’s inventory.

The following day, Richelieu placed a thick stack of reports on Setsuna’s desk.

”Commander, I organized a round of inventory checks yesterday with the shipgirls. This report contains all the materials we currently possess. Please have a look.”

As the fleet’s secretary ship, Richelieu diligently tracked and reported every detail of the settlement’s operations, including resource reserves, personnel changes, material consumption, and production status.

Her neat, elegant handwriting filled the pages, listing each item clearly and methodically, reflecting her impeccable work ethic.

”Thanks for the hard work.”

Setsuna opened the report.

As the commander, it was his responsibility to oversee resource levels and consumption and plan the settlement’s future direction accordingly.

Strategic Resources:

• Iron Ore: Reserves: 10,000 tons; Monthly Production: 450,000 tons.

• Coal: Reserves: 15,000 tons; Monthly Production: 320,000 tons.

• Tin Ore: Reserves: 2,000 tons; Monthly Production: 1,200 tons.

Additionally, there were refined resources such as aluminum, magnesium, copper, and even uranium.

Under Essex’s leadership, the expeditionary fleet had established mining and smelting facilities in the resource-rich Balkan region.

Despite having limited manpower, the combined efforts of the Bulins and Manjuus had resulted in production levels comparable to a mid-sized mining corporation.

Every fortnight, Bulin-operated fleets transported massive loads of ore from Athens to Constantinople, fueling the city’s development.

”Not bad. Next time we open a dimensional portal, let’s request more personnel from the main base.”

Setsuna was satisfied with the progress of the mining teams.

Iron and coal were the foundations of modern industry. The higher the output, the faster future infrastructure projects could proceed.

Equipment Inventory:

• Carrier-Based Aircraft: 1,612 units.

• Torpedo Bombers: 582 units.

• Fighters: [Varied models, see appendix].

• Torpedoes:

• Total: 3,240 units.610mm Torpedoes: 240 units.

• Quadruple 533mm Magnetic Torpedoes: 330 units.

• 155mm Self-Propelled Artillery: 160 units.

• Aerial Bombs: 4,200 units.

• Hydrogen Bombs: 26 units.

”Hydrogen bombs?”

Setsuna blinked, rereading the entry.

When the expeditionary fleet set out, the harbor had equipped them with enough supplies to last for years. But this?

”Where did the hydrogen bombs come from?”

”Oh, Akashi made them using captured Siren technology,” Richelieu explained after a moment of thought.

”Headquarters was worried we’d encounter powerful enemies, so every carrier shipgirl was assigned a few.”

”…”

”So Taihou, Formidable, Essex, and Illustrious… all have nuclear strike capabilities?”

Setsuna suddenly recalled the skirmish between Richelieu and Taihou over the secretary ship position and shuddered.

Thankfully, no one had lost their temper enough to use those weapons.

”This is fantastic. Not only do we have thousands of planes, hundreds of artillery pieces, and an obscene amount of torpedoes, but we also have nukes.”

The sheer military power at their disposal was staggering.

On Earth, this kind of strength would easily earn them a seat at the table of the permanent members of the U.N. Security Council, placing them among the world’s most influential powers.

Then, his eyes moved to the next section.

Food Supplies:

• Rice: 20 kilograms.

• Corn: 10 kilograms.

• Various Grain Seeds: [Detailed list in appendix].

”?”

Unlike the endless lists of aircraft, torpedoes, and bombs, the food inventory was astonishingly sparse.

Setsuna double-checked to confirm the units listed were kilograms, not tons or megatons.

”These were retrieved from your birthplace,” Richelieu explained.

”…”

It all made sense now.

Shipgirls didn’t require food to survive. Occasionally, they indulged in snacks, but even that was more of a recreational activity.

Their hydrogen bomb reserves outweighed their rice stocks.

”Commander, what do you think our next steps should be?”

After Setsuna finished reviewing the report, Richelieu waited for his decision on the settlement’s direction.

Setsuna rubbed his forehead, contemplating.

Their economy was virtually nonexistent, while their stockpile of weapons was enough to equip an entire naval armada, with more firepower than most nations could ever hope to possess.

Two clear paths emerged:

”Right now, we have two options.”

”Option one: Focus on developing agriculture and light industry to prepare for the future.”

”Option two: Conquer our neighbors, turn them into tributary states, and engage in sustainable resource extraction.”

For now, Setsuna chose the first option.

The primary reason was that his dimensional travel ability was still on cooldown, making it impossible to engage in interdimensional conquests.

The secondary reason was his identity as a citizen of a certain agricultural civilization. Starting anew and rebuilding a world without farming felt like a betrayal of his roots.

His DNA rebelled against the idea.

Even if the shipgirls didn’t need food, it was prudent to establish agricultural systems for long-term security.

Who knew when visitors from other worlds might arrive? Offering them fuel and coolant wouldn’t make for great hospitality.

”So, does anyone here know how to farm?”

Setsuna gathered the expeditionary fleet shipgirls.

”Nope.”

Their heads shook in unison like a chorus of rattles.

”Well, um, I might know a little,” a voice hesitated.

”Sometimes I plant things in the port’s garden,” Ning Hai and Ping Hai raised their hands shyly.

”Oh?”

Setsuna looked at the two sisters, unsurprised that the Dragon Empery shipgirls had unique skill sets.

”What can you grow?”

”Wheat, rice, cabbage, chili peppers… I’ve dabbled in growing fruits too. If we have seeds, I could try apples, strawberries, or watermelons,” Ning Hai answered humbly.

”That’s not ’a little’—you know everything!”

Setsuna marveled at their humility, akin to top students apologizing for scoring only 98 out of 100.

He patted their shoulders.

”Ning Hai, Ping Hai, I hereby appoint you as acting ministers of agriculture. The future of farming here is in your hands.”

”Just us two?” Ping Hai blinked, feeling like an understaffed department.

”You’ll each get 20 Manjuu as assistants.”

”The little yellow chickens can handle heavy lifting and mining, so with some training, they should be able to farm too.”

...

”Here, follow my lead. First, use the plow to turn the soil, then plant the seeds.”

”Keep the rows 30 centimeters apart. Each corn plant should have a 20-centimeter gap. Fertilize every 10 days. Got it?”

A few days later, in the designated agricultural zone outside Constantinople, Ning Hai and Ping Hai were busy teaching the Manjuus how to farm.

Bending over with seeds in one hand and tools in the other, they demonstrated the process step by step.

Anyone who happened to walk by and witness this scene might have exclaimed in disbelief, ”Unbelievable! Someone’s teaching chickens to farm?!”

Around the two sisters, a group of Manjuus watched intently, their round eyes filled with curiosity.

”...”

”Did you understand?” Ning Hai asked after finishing the demonstration.

”Chirp!” A Manjuu nodded enthusiastically.

”Then give it a try.” Ning Hai handed over a handful of seeds to the small bird.

The Manjuu pretended to think for a few seconds before promptly gobbling up the seeds in one bite.

Clonk!

”Chirp!”

Ning Hai smacked it on the head with her knuckle.

”I didn’t tell you to eat them! You’re supposed to plant them!”

She fished out a small dried fish from her pocket.

”Plant the seeds, you get a treat. Eat the seeds, you get whacked. Got it?”

”Chirp?”

After a few more rounds of correction, the Manjuu seemed to grasp the connection between its actions and the consequences. Every time it ate a seed, it would get clobbered. If it planted the seed, it would earn a dried fish.

While their intelligence wasn’t particularly high, their instinct to avoid harm and seek rewards kicked in. Before long, they began using their claws to dig into the soil or even attempted to use tools to farm.

”Is this Pavlov’s dog experiment?!”

Nearby shipgirls watched in awe.

Ning Hai and Ping Hai’s teaching method seemed oddly effective. Back at the port, no one had ever imagined that these adorable little Manjuus could be taught to farm.

”Hmm…”

Ping Hai crossed her arms and pondered as she watched Ning Hai train the Manjuus as if they were puppies.

”Manual farming seems way too slow. How about we ask Akashi to build some farming equipment so the Manjuus can operate machinery themselves?”

She pictured an expansive plain filled with Manjuus driving tractors to harvest crops. The image of their future settlement’s aesthetic took on a strangely whimsical charm.

Meanwhile, as Ning Hai and Ping Hai busied themselves training the Manjuus, Setsuna reopened the settlement’s Overview Interface to check on its progress.

[Civilization Overview]

• Civilization Type: Technological Civilization

• Technological Level: Pre-Space Age

• Population: 331

• Species: Humans, Shipgirls

• Territory: 5,220 square kilometers

From the moment he had been stranded here, less than two months had passed, yet the settlement had advanced at breakneck speed to the pre-space age.

Or perhaps it would be more accurate to call it the Magic Age.

After all, Azur Lane’s technology defied the strict definition of science.

It seemed that starting with nothing wasn’t such a disadvantage when you had good neighbors to rely on.

The 300+ population consisted of himself, the shipgirls, and the Bulins. The Manjuus, treated as pets, were excluded from the count.

The 5,000+ square kilometers of territory likely encompassed the newly constructed naval base and its surrounding waters.

The land-based city hadn’t even been built yet. If it had, the area would’ve been far larger.

The fastest progress, of course, was in technology.

With Azur Lane’s support, they had leapt past the Bronze Age, Steam Age, and Electrical Age straight into the Pre-Space Age, with just one final step to fully enter the Space Age.

As for what lay beyond, more advanced civilizations perhaps, it was anyone’s guess.

”Hmm?”

Setsuna noticed a new Species Index feature in the Species section.

”A creature index?”

Curious, he opened the entry for Shipgirls.

Azur Lane Shipgirls:

Born from the Wisdom Cube, they exist between artificial intelligence and magical lifeforms. Adapted for marine environments, they excel at naval warfare. Most belong to the Lawful Good alignment and can efficiently utilize a variety of tech-based equipment.

”Interesting.”

The index provided handy summaries of each species’ traits, giving him a clearer understanding of their capabilities.

The shipgirls preferred to stay near the ocean. Their combat strength primarily came from their rigging, which could be upgraded with advanced weaponry. This made them quintessentially tech-aligned beings.

The Lawful Good alignment was also easy to understand.

Shipgirls were generally straightforward and kind-hearted. Even those like Akagi, Taihou, or Roon—known for their eccentric personalities—were more flawed in character than truly evil.

”Are there other creatures too?”

Setsuna noticed many entries in the index were grayed out, indicating they hadn’t been unlocked yet.

[Spirits, Heroic Spirits, Valkyries, Herrschers, Magical Girls, Catgirls, Dragon Girls…]

”Wow, there are so many species to collect?!”

[Collecting enough unique species would unlock special rewards]

[Please expand your empire, enhance biodiversity, and enrich your civilization!]

”…”

”So, this is basically Wife Pokémon?”

”Wait a second.”

Looking at the stats panel, Setsuna suddenly remembered something important.

Initial Quest.

It required recruiting 20 individuals and establishing a civilization.

He had the settlement, and there were more than enough people.

Even excluding the Bulins and Manjuus, the expeditionary fleet alone had 30 shipgirls.

”Why isn’t the mission completed yet?”

”Do shipgirls not count? That makes it impossible to finish!”

”Hey! Hello? Is this a bug in the mission system?”

[Confirmation.]

A mechanical voice responded.

• Mission Objective 1: Recruit 20 Companions.

• Complete.

• Mission Objective 2: Establish a Civilization.

• Incomplete.

”What’s that supposed to mean?”

[Your settlement lacks distinguishing features to qualify as a civilization.]

[Please upgrade your colony into a fully recognized civilization.]