Crossover Shipgirls: Building a Dimensional Empire from Scratch

Inside the pocket-universe city, everyone clicked their tongues in amazement.

In the original story, Cheng Xin’s Universe No. 647 only included a house and a plot of farmland, but here it was an entire city.

Moreover, due to the peculiar space-creation technology, no matter which end of the city you set out from, once you reached the edge, you would return to the starting point.

It was a small world bubble.

Although its area wasn’t large, its principles were completely identical to those of the universe outside.

”How did this sun and sky come about?”

Yat Sen activated her sensors and discovered the sky wasn’t actually that far away.

”Holographic simulation.”

Kayo Senju answered.

”The pocket-universe itself is a cube about 200 kilometers on each side. Because of spacetime distortion, you can never truly reach its boundary.”

”It has its own internal circulation system, powered by a dark matter engine and a cube reactor.”

”Oh.”

The group nodded in understanding.

After patrolling the streets once, they saw that most of the living facilities had already been completed. The Bulins and Angeloids were busy finishing the last touches.

”Additionally, some physical constants and spacetime laws in the pocket-universe can be customized.”

Grey walked as she opened a holographic interface.

Several conspicuous options were displayed on it:

[Spacetime Curvature: 1 (default)]

[Gravity: 1G (default)]

[Atmospheric Composition: ...]

”The timeline inside the pocket-universe is completely independent from the universe. By adjusting the spacetime curvature here, we can achieve effects similar to the Eternal Snowfall.”

Grey explained.

”If the curvature is adjusted high enough—tens of billions of times or more—while we spend a short while here, in the universe we might witness the end within just a few years.”

”Based on estimates… well, in half a year the sun would run through its life cycle, turning into a white dwarf. Within two years the solar system would collapse, and in ten years the entire universe would contract into a singularity.”

”If the curvature is adjusted lower, it’ll be similar to the Eternal Snowfall. Basically, like when the Commander throws a party and uses his authority.”

Setsuna didn’t touch the spacetime curvature.

In the pocket-universe, one could truly idle away as if eons passed in the blink of an eye.

Staying here for a short while could equal tens of millions or even billions of years in the outside world.

”As for gravity, it’s straightforward. The gravity here is simulated and can be freely adjusted.”

Grey tapped the panel, changing it to 0.2 standard gravity.

The little shipgirls gave a light jump, and without using any thrusters, floated into midair.

Ooooh—

Chirp?!

Even the little yellow chicks farming at the city’s edge floated up into the air, flapping their wings frantically, chirping in panic.

”Can we contact the universe from inside the pocket-universe?”

Richelieu asked.

She found all her communication devices unusable.

”No.”

Grey shook her head.

”This is essentially another universe. Aside from the Commander using his authority to connect with the outside, no information can pass through.”

”However, the universe can send ultramembrane broadcasts to all pocket-universes, just like how the final Return Movement broadcast civilizations did.”

”But sending an ultramembrane broadcast that a pocket-universe can receive would consume an astronomical amount of energy—about enough to convert the entire Milky Way into pure energy.”

A nanobot counted on its fingers.

”Compared to the sub-light natives, our tech is advanced. If converted into Wisdom Cube energy, emptying our reserves should allow one full-universe, cross-world broadcast…”

”Are you insane?! There’s no one else in this universe—who would you even be sending a broadcast to?!”

Richelieu smacked Grey on the head.

The group continued to tour the little world.

Whether city construction, agriculture, or industry, this place was a self-contained realm.

Without external interference, it could persist until the end of time.

—And external forces could never interfere here. Even if the universe perished, the pocket-universe would remain.

It was the ultimate refuge, a last resort created by god-tier civilizations in the Three-Body world.

”Amazing, truly amazing…”

The companions marveled in awe.

After exploring every corner of the city, Grey finally opened the exit, and the group reluctantly walked out.

”We’ll designate this universe as Universe No. 1, city-level in scale.”

Kayo Senju gave a summary report.

”Constructing Universe No. 1 consumed resources equal to about five times its total volume. Hmm, that’s roughly the equivalent of an aircraft fleet?”

”Hiss—”

The simple conversion startled everyone.

Creating a universe out of nothing was naturally not cheap.

Even if it was only a small city, the Bulins could finish in one or two weeks, but the resources expended were very real.

To construct a solar-system-sized world inside a pocket-universe would require dismantling five or six suns, maybe more.

”Universe No. 1 will be handed over to the research department for study. See if it can be improved—cross-universe communication functions, for example.”

Setsuna thought it over and assigned the little universe to the researchers.

”As for follow-up construction, keep the scale at city-level for now. When the technology matures, we can move on to planetary- or star-system-level.”

”As for galaxy-level, universe-level… cough, let’s wait until we have a pump before considering that.”

”Also, I have a bold idea: try merging a pocket-universe with ship rigging and see what happens.”

He came up with another wild idea. After all, combining technologies from two worlds was the Starsea Empire’s greatest strength.

”Alright.”

”Sounds a bit difficult, but we’ll try later…”

The research lolis nodded.

”...”

”Wait a second.”

”Stuffing a pocket-universe into the Eternal Snowfall?! We used to have shipgirls carried by warships—are we now moving on to universes carried by ships?”

Richelieu froze.

She couldn’t help imagining a scenario:

Every cabin on the Eternal Snowfall was an entire world.

Opening a door would lead to a brand-new universe.

The starship itself would be a multiverse composite body.

It would carry countless universes across the stars.

At a mere thought, galaxies shattered and universes perished.

”I thought the Juggernaut’s next upgrade would be a stellar-class warship or something like that, but it’s jumping straight to something this ridiculous?!”

”A multiverse battleship?! Burning with cosmos?!”

Grey felt the Eternal Snowfall’s upgrade route had gone far beyond imagination.

”Are you a technological Saint Seiya now?!”

”More like a pay-to-win version.”

Gudako narrowed her eyes and muttered.

”Do you know how many resources it costs to build just one pocket-universe?! If we play like that, we’d have to drain all our neighbors dry!”

”And stacking multiple world powers onto oneself like that… isn’t that basically a god?”

”A technological god?!”

...

The uproar over pocket-universe technology lasted for a while in the capital.

Many lined up to visit the little world.

Aside from its peculiar space structure, there wasn’t much difference from the universe.

The empire’s research department would conduct in-depth studies of the bubble-world.

Setsuna’s wild idea had left the research lolis with a project hundreds of times more difficult than faster-than-light travel.

—Stuffing a pocket-universe into the Eternal Snowfall.

The Commander had a habit of wanting to install anything new into his flagship, whether technological or magical. Everyone was used to it.

But this wasn’t as simple as placing a pocket-universe entrance inside. The Eternal Snowfall would have to actually contain an entire world.

”...”

”In three-dimensional terms, it might be possible for the Juggernaut to carry a city-level bubble-world… but for planetary or larger scales, the space is clearly insufficient…”

”Unless… unless…”

Kayo Senju toyed with her golden hair in the research center while pondering.

”Unless we elevate the Eternal Snowfall to higher dimensions? Transform it into four-dimensional, five-dimensional, or beyond…?”

”Aaaaah, that sounds even harder!!!”

The research lolis pulled at their hair in frustration.

”Do your best—our Commander’s future depends on you.”

The nanobots, acting as teachers, cheered the group on.

”We can’t keep it up, it’s too hard…”

Kayo Senju looked utterly lifeless.

”...”

”The Commander said you’ve done a huge favor for him and the Empire. When you grow up, he’ll marry you.”

Grey decided to encourage the lolis.

”Really?! Onii-chan said that?!…”

A roomful of research lolis instantly lit up, eyes sparkling as though injected with chicken blood.

”Actually, we could do it right now too.”

Several lolis immediately raised their hands and shouted.

”It’s true, there’s even a record.”

Grey casually pulled up a forged chat log, making things up without hesitation.

”Even if it’s fake, once you succeed in your research, would the Commander really refuse such a small request?”

”See? Your contributions are obvious to everyone. We’re all grateful to you. Just find a chance to act spoiled with the Commander, and it’ll happen naturally.”

Every word struck directly at the lolis’ weak points, stirring a noisy uproar.

Ooooh—

Including Kayo Senju, the research lolis suddenly felt full of power.

”Everyone, let’s work overtime this year and next! Strive to hold the wedding the year after!”

”Oooooooh!!! Burn with passion!!! For the sake of becoming the Commander’s brides, charge!!!”

”???”

Passing by, Ark Royal was shocked.

”Why can the Commander have so many lolis, while just getting close to one would get me arrested and thrown into solitary?!”

”If the Commander breaks the law, shouldn’t he be punished the same as us shipgirls?! My cellmate?!”

Smack—

Bismarck firmly pressed a hand on her shoulder.

”Are you done talking? If so, come with me.”

”These research lolis will grow into young maidens in a few years, alright? What’s the problem?”

”Maidens?”

Ark Royal instantly lost interest.

”Forget it, I’ll go look for destroyer little sisters instead.”

”Oh? Is that a criminal premonition I just heard?”

Bismarck raised an eyebrow.

”You’re under arrest. Serve your sentence first before thanking me.”

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