Crossover Shipgirls: Building a Dimensional Empire from Scratch

It took Setsuna quite some effort to stop little Griseo’s mind from wandering too far.

She was completely immersed in her art, and her understanding of the outside world was unlike that of ordinary people.

Or rather, her perception of others seemed to touch upon their truest essence.

Among everyone in the capital, Griseo was probably the one most sensitive to the presence of the Outer God girls.

”You need to pay more attention to how they look now, don’t let your imagination run wild.”

Setsuna gently patted Griseo’s head.

Weren’t those beautiful girls enough to look at? Why dwell so much on what their true forms were?

Shipgirls’ true forms were battleships, after all, and Tohru’s true form was a mighty dragon.

Yet they all partied happily aboard the Eternal Snowfall.

Well... slightly better than eldritch abominations, maybe.

”Oh...”

Little Griseo nodded faintly, as if she half-understood.

She began gathering her paintings, rolling up the indescribable colors and lines on the canvases, sealing them carefully into tubes.

Each was neatly labeled and stacked on the shelves nearby.

”Now that I look at it, you’ve made quite a lot of works...”

Setsuna glanced around.

In Griseo’s studio, the bookshelves were filled entirely with rolled canvases.

She had categorized them by the worlds she had visited, neatly preserving each collection.

He picked up two of them to take a look.

Some depicted the capital city; others portrayed different vassal worlds.

Griseo’s art style was incredibly diverse—some were realistic enough for Setsuna to immediately recognize places like Constantinople or other domains, while others were completely abstract, her use of color and form beyond his comprehension.

There were even a few portraits among them.

”Is this... Hua?”

”And this one—Tohru and Mio?”

The more distinctive ones, he could identify, but most of the portraits he couldn’t tell who they were meant to be.

”Mm.”

Griseo nodded.

”Sometimes I go to other worlds to paint from life, to record what I see there.”

”I’m very happy living here, so I thought...”

”I thought... someday, I could show all the colors of these worlds to Sister Elysia and Mother Aponia.”

”Oh—”

Setsuna hadn’t expected Griseo to think about that.

Even now, the little girl still carried her responsibilities as the Stars Flame Chaser, remembering her companions from before.

”Commander, you said before that I’d get to see them again someday, right?”

Griseo looked up, her clear and innocent eyes meeting his.

She remembered the promise he had once made to her and Fu Hua.

”Yes.”

Setsuna smiled, hugging Griseo and pinching her soft cheeks.

”Yes—and it won’t be long now.”

He realized he had quite a long list of things waiting for him to do.

But once the multidimensional starship and the massive psionic transfer array were both completed, everything would fall into place.

If necessary, he could even ask Yog-Sothoth for assistance.

”Hmm...”

Griseo puffed her cheeks slightly, tilting her head in thought.

She didn’t really understand the technical side of things, but she had seen too many miracles within the Starsea Empire.

To her, if Setsuna promised something, it was as good as done.

”If only I were a little older... I could help Commander Onii-chan like Sister Hua does...”

Little Griseo murmured softly.

”It’s okay.”

Setsuna pinched her cute face again.

”Once we gain the ability to manipulate timelines, we can always find an older Griseo somewhere.”

”Eh?”

...

The next day.

The Outer Gods from Nyaruko’s universe officially joined the Starsea Empire.

In many ways, aside from their peculiar way of thinking, they were no different from normal people.

They fit into their new lives almost seamlessly.

”Lady Akashi, please! Teach me the sacred art of game creation!”

In Akashi’s workshop, Luhy Distone came personally, following right behind the repair cat, begging to be taken in as a disciple.

As the former head of the First Hardware Research and Development Department of Cthulhu Corp’s gaming division, she was utterly amazed by Akashi’s game design and console engineering skills.

With the unbeatable Bulin assisting, they could absolutely create the most powerful gaming console in the entire universe.

”I’m gonna need tuition fees, nya~”

Akashi twitched her ears, unable to resist Luhy’s persistence.

”I’m super busy, you know? If I have to take time off work to teach you, I need some extra compensation.”

”Hmm?...”

Luhy searched through her pockets. Back when she was still a corporate wage slave, she barely had anything to her name—and since the Starsea Empire didn’t even use currency, she obviously had no savings.

Then suddenly, an idea struck her.

”How about I teach you some magic instead?”

”Nya? Got any spells that turn things into gold?”

Akashi’s ears perked up in excitement.

”Ah... not quite. I’m one of the Great Old Ones, you see.”

Luhy pulled out an old, yellowed book that looked suspiciously cursed.

”I can teach you some Cthulhu-style spells.”

”For example—summoning Cthulhi, shattering an enemy’s sanity, calling upon Faceless Ones or Byakhee, creating ghouls or Deep Ones, and more...”

”?”

”Meoww??!!”

”The Magic Academy’s that way, left turn out the door! Go find Mio instead, nya!!!”

...

In the Magic Academy—

As the headmistress, the Spirit of Origin, Mio, watched with a perplexed expression as the Outer God girls demonstrated their so-called ”magic.”

Or more accurately, divine power.

Cthulhu-style sorcery radiated nothing but ominous, chaotic energy from start to finish.

It included (but was not limited to) summoning demons and servants, invoking the Great Old Ones and Outer Gods, and performing necromantic arts such as limb decay curses.

”Whoa—”

The Crimson Demon loli showed an alarming amount of interest in these spells.

”Mio-nee, these spells are super strong, aren’t they?!”

”Hmmm... summoning Outer Gods... surely that’s way stronger than the demons we can call up back in our world?!”

Komekko waved her wand and began chanting a spell.

Boom—

Black mist enveloped the area.

A massive, amorphous creature resembling a gigantic slime descended from the void.

Its surface shimmered faintly as countless glowing green eyes formed and dissolved across its body.

Everyone nearby instantly felt their sanity plummet.

”Wow, you actually summoned a Shoggoth on your first try—amazing.”

Shub-chan clapped for the Crimson Demon girl’s impressive magical talent.

”With more practice, you might even summon something stronger next time!”

”Strictly forbidden to cast any Cthulhu-type spells within the capital!!!”

Mio and Elma’s mouths twitched.

They realized the academy might soon need to open a new subject—

A forbidden branch of magic.

Cthulhu-class magic.

Thankfully, with the Outer Gods themselves supervising, practicing these spells wouldn’t end in catastrophic accidents the way it would for humans.

The Starsea Empire’s magicians were about to step into uncharted territory.

...

At the top floor of the Administrative Center—

Setsuna reviewed the incoming reports with satisfaction.

Thanks to the Outer Gods’ surprisingly lawful and good-natured behavior, they got along well with their new friends in the capital.

Some went shopping, others stayed home gaming.

The Magic Academy had even gained a brand new field of study.

While most mages summoned elemental creatures or spirits, the Crimson Demon girl had jumped straight to summoning the Great Old Ones and Starspawn.

That alone raised the magical prestige by several tiers.

”Hmm... so, that wraps up the Nyaruko world then?”

He checked off another item from his to-do list.

There was no need to conquer the entire Nyaruko universe—as long as the Outer Gods were here, that was enough.

Two of the Three Pillars were already present; only Azathoth and Yog-Sothoth remained at work on their side.

Setsuna was confident that once they took a vacation and visited the Starsea Empire, they’d never want to leave.

”Next up...”

He was planning his next course of action when—

Vrrr—

A low hum resonated from the distant starship docks.

A small lavender-colored ship touched down on the landing platform.

Judging by the hull markings, it came from the Eagle Union carrier, Essex.

Shhh—

A holographic window opened before him.

”Commander! I just returned from the Fifth Singularity!!!”

Gudako’s face appeared on the screen, smiling brightly.

”Mission complete! Oh, and um... one of the Heroic Spirits seems to be your wife—she even came with her wedding dress on!”

”?”

...

”Hi hi hi, everyone, welcome to the Starsea Empire—!”

At the starship landing base—

Clack—

As the ship’s hatch slowly opened, Gudako was the first to hop down the ramp, waving energetically to the group behind her.

A few Heroic Spirits followed, still not entirely used to the high-tech environment.

They stepped down one by one, cautiously testing each step.

”So bright—!”

The dazzling sunlight and the sight of numerous floating anti-gravity buildings made it hard to keep their eyes open.

Not far away, several starships were lifting off, their engines blasting out waves of scorching air.

At the front of the group, a tall woman with purple hair and red eyes—dressed in a skintight bodysuit and black tights—instinctively raised her hand to shield her eyes.

Her commanding figure exuded a sharp aura, and her outfit only accentuated her striking allure.

”Mmm—”

As Scáthach carefully surveyed the massive cityscape before her, she quickly realized she had arrived in a place far beyond comprehension.

Everything here was alien to a Heroic Spirit: the Angeloids gliding through the air, the fleets of ships descending from the skies, the sheer scale of technological power.

It surpassed anything from any era she had known.

”Mmm, this place is far more prosperous than my Rome ever was, hm?”

Beside her, a blonde-haired, blue-eyed Heroic Spirit peeked out curiously.

Her appearance was identical to Nero’s—but what truly drew everyone’s gaze was her attire: a pure white wedding gown.

A delicate veil adorned her head like a crown, and a long, flowing train swept elegantly behind her.

She looked every bit like a bride walking down the aisle.

”...”

The other Heroic Spirits behind them remained silent, equally awestruck as they took in the splendor of the capital.

”Well? Didn’t I tell you? The Starsea Empire is tens of thousands of times better than the worlds you’ve been in.”

Gudako puffed up her chest proudly.

Convincing Heroic Spirits to sign contracts and luring them to another universe took real skill.

Luckily, the Starsea Empire was vast and resource-rich—able to fulfill nearly every wish a Heroic Spirit could have.

After showing them some of the Empire’s ridiculous technology and magic, their curiosity usually won out, and they followed her without hesitation.

”Let’s go report to the Commander, Ritsuka Fujimaru.”

”Our mission took longer than expected this time. I believe we should give the Commander a full debrief.”

Beside her, a twin-tailed shipgirl with an equally fierce aura spoke in a calm, professional tone.

”Yes, yes...”

Gudako waved a hand and led the Heroic Spirits from the Fifth Singularity aboard a shuttlecraft.

They flew across the vast cityscape before landing at the docking platform of the Administrative Center.

”Alright, tidy up your outfits, put away your weapons, and follow me to meet the Commander.”

”Mm...”

Inside the Administrative Center, shipgirls and little lolis bustled about everywhere.

When they saw the new arrivals, no one even batted an eye—by now, new otherworldly guests were nothing new.

”Master’s waiting for you inside. Please, go on in.”

Icarus pointed them toward the main office.

”Commander!!!”

”Mission complete, I’m back!!!”

Thump—

Gudako slammed her palms onto Setsuna’s desk, grinning proudly.

She grabbed the drink next to him, took a few gulps, and snatched a few snacks to munch on.

”This Singularity was pretty interesting—mechanized infantry and all—but still kinda weak, tsk.”

”Well done.”

Setsuna smiled in response.

The Fifth Singularity—North American Mythic War—had involved fighting against Edison’s mechanical army and the Mad King.

It might’ve sounded high-tech, but since he had sent a squadron of carriers and battleship-class shipgirls, plus Gudako piloting the Strelitzia, he could already imagine what had happened.

She probably went full mecha mode and bombarded everything in sight, leaving the locals completely dumbfounded.

”See? Not one missing.”

Gudako gestured proudly, calling the Heroic Spirits over.

”I thought Heroic Spirits only had an original, an Alter, or maybe a Lily version—but now there’s even a Bride version?”

”They’re two separate people?!”

The shipgirls stared in confusion at the Nero in a wedding gown.

She looked identical to the one from the Second Singularity—but the pure white bridal outfit made her presence even more captivating.

”Heroic Spirits are just different manifestations of the same person under different circumstances—it’s not strange. Who knows, maybe there’ll even be a Beast Nero someday.”

Setsuna chuckled.

”Mmm? You look exactly like me? No, wait—you are me?...”

The original Nero finally noticed the Bride Nero standing beside her.

Not only was she dressed entirely in white, but even her sword had changed from crimson to silver.

The two Neros locked eyes, staring each other down.

”I am Nero Claudius, Fifth Emperor of the Roman Empire. And you are?”

”I too am the Emperor of Rome! I am the newly adorned, more powerful, more magnificent Bride Nero!!”

”Eh?!”

”In life, I never found my fated partner before my untimely death. Even as an emperor, basking in endless glory, I never fulfilled my wish to become a bride.”

”...So before my death, I prepared this wedding dress.”

Bride Nero puffed her cheeks as she spoke.

”My Master told me there was someone here who could grant that wish—that he was my destined partner! So, I followed her here.”

As she spoke, her eyes swept over Setsuna—up and down, carefully examining him.

”Mmm, you are the Emperor of the Starsea Empire, yes? Your status matches mine quite well...”

”It seems you rule a vast empire. How does it compare to Rome, I wonder...?”

Bride Nero had come seeking her destined partner—and Gudako had lured her in with that very promise.

—Human Evil wasn’t lying when she said the Starsea Empire had the finest men in the universe.

Thwack—

The original Nero smacked Bride Nero lightly on the head.

”How could you ask such a foolish question?! My Empire can’t even compare to this place! Such short-sightedness... tsk.”

”...”

Setsuna and the shipgirls both facepalmed as the two Neros started bickering.

Bride Nero embodied the version of Nero that longed for love and a wedding with her destined one.

The other Nero, in contrast, was closer to her historical self.

Unlike Jeanne d’Arc and Jeanne Alter, these two were remarkably similar in both personality and temperament.

And so, through a rather spirited conversation with herself, the two quickly came to accept each other.

”Mmm, from now on, you must listen to our Master’s words.”

”Mmm, then when may I hold my wedding with him? Since the other me fancies this man, he must surely be the right one!”

”Wait!! Too soon! If you marry the Master, what about me?! I should get a wedding dress too!”

”Mmm, am I to marry the same man twice...?”

The two Neros crowded around Setsuna, one on each side.

”Mmm, Master, tell us— which version of me do you prefer?!”

”...”

Setsuna thought both Neros were great.

”Mmm, I like both. Twice the Nero, twice the happiness.”

”Wait—why did I just say ’mmm’? I must’ve caught it from the Mmm Monster, mmm.”

...

After the Neros finally settled down, Setsuna turned his attention to the remaining Heroic Spirits.

As usual, Gudako had brought back all the Servants from the Fifth Singularity. Technically speaking, she was their true Master—but Setsuna didn’t really care.

”Greetings, Commander. I am Florence Nightingale. Now that I am here, you may rest assured—I shall save all lives.”

”I noticed there are many children in your nation. Do they have adequate medical resources? The greater the empire, the greater its responsibility to safeguard the health of its people.”

A woman in a military-style uniform, long boots, and a medical satchel gave Setsuna a sharp look.

Unsurprisingly, it was none other than the legendary nurse herself—Florence Nightingale.

Every nursing academy’s students swore the Nightingale Pledge before graduation—a legacy that bore her name.

”Uh... medical personnel? Then you should probably report to the Department of Life Sciences. Anyway, the times have changed—our medicine’s a bit... beyond what you’d expect.”

Still, having the founder of modern nursing within the capital certainly boosted the Empire’s prestige.

”...Oh...”

Scáthach’s gaze swept from Setsuna to the shipgirls, Spirits, and other companions around him.

How strange.

She had never seen beings like them before—she couldn’t even tell what races they were.

Out of courtesy, she still gave a polite nod.

”From the Land of Shadows, I am called Scáthach.”

”They said I could meet power here far beyond my own—and perhaps even one who could kill me. Is that true?”

Her tone carried both irony and a faint sense of yearning.

”Hmm?”

Setsuna blinked.

He’d met people who came seeking adventure, strength, food, research, entertainment—but this was a first.

Someone coming specifically to die.

”...”

Tohru crossed her arms, staring at Scáthach like she was insane.

”So you’re saying... you came here to find someone who could kill you?”

”Queen of the Land of Shadows, huh? You’ve got guts.”

—

—

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