Crossover Shipgirls: Building a Dimensional Empire from Scratch

Two Days Later

Open Seas

A black-and-red armored aircraft carrier sailed steadily through the Atlantic Ocean, cutting through the waves with ease.

Despite the turbulent winds and waves of the Bay of Biscay, the 30,000-ton vessel remained as steady as a mountain, with barely a hint of motion to disturb those aboard.

With the wait for their return stretching out ahead of them, the group had no intention of roughing it in the wilderness or staying in the crude accommodations of a medieval inn. Living aboard a ship girl’s hull was far more comfortable.

Taihou had summoned her true form—a massive aircraft carrier—and brought everyone along for a cruise through the 15th-century Atlantic Ocean.

It was a perfect way to relax after completing the mission.

After all, the locals in this era had little to no capacity for oceanic exploration. Even if an occasional fleet from another nation spotted them, a few flights of carrier-based aircraft were enough to send them scurrying.

No medieval admiral in their right mind would dare challenge an aircraft carrier.

”Amazing projection magecraft,” Jeanne d’Arc marveled as she toured the interior of Taihou’s hull.

The space was completely designed in a Japanese style, exquisitely decorated and equipped with all the conveniences of modern living.

This level of magecraft—creating objects out of thin air and resizing weapons at will—was far beyond anything she had ever seen in her experience as a Ruler.

”Hey—”

”Why are you tagging along with that guy to another world?!”

Jeanne Alter shot White Jeanne a glare, her tone anything but friendly.

”Why not?”

”This France has already been saved. I’ve heard that the Master’s world is a ruined one,” White Jeanne replied matter-of-factly.

”If I have the duty to save one nation, then I should also do everything I can to help save another world in need.”

Her response was perfectly natural and in line with her unwavering nature as a saint.

She and Jeanne Alter were polar opposites in every possible way—a true ”Holy Maiden” through and through.

”...”

”Ugh, how moving. I think I’m gonna puke,” Jeanne Alter muttered, slumping onto the couch with a look of utter resignation.

”Master, if you ever need someone to burn people alive or destroy nations, leave it to me. But please, I beg you, don’t make me work alongside her.”

”...”

”In that case, maybe I’ll summon Alter Artoria next time and have the two of you team up,” Setsuna said, glancing at the three Heroic Spirits.

Jeanne Alter, Jeanne d’Arc, and Artoria Pendragon… if he added Alter Artoria into the mix, they’d form two perfect black-and-white pairs.

Traveling with two sets of black-and-white combos would be ridiculously cool and flashy.

The only small issue was that none of these individuals seemed to get along with each other.

Late Night

On the Bridge’s Upper Deck.

Setsuna sat on the balcony, gazing out at the starry sky and the vast expanse of ocean in the distance.

His room had been deliberately arranged at the top of the command tower, lavishly outfitted like a presidential suite.

The medieval night was especially tranquil. Being on the open sea, there wasn’t a sound to be heard for tens of kilometers beyond the rhythmic crashing of the waves.

The distant land lay silent as well. This era lacked the lively nightlife of modern times.

”Commander, you’re still awake?”

Suddenly, a familiar voice came from behind him.

Taihou, now dressed in her casual attire, quietly approached him.

She wore a short kimono that barely reached her thighs, leaving them exposed and the curve of her legs fully visible.

”I thought I locked the door…”

Setsuna chuckled helplessly, surprised by her appearance.

He was sure he’d developed the habit of locking doors without fail.

”This is Taihou’s ship, after all… Besides, even the keys to the Commander’s office are with me~,” Taihou said playfully as she sat beside him, leaning her head against his shoulder.

”Commander, what are you thinking about?”

”...”

To his surprise, Taihou wasn’t acting like her usual yandere self. Instead, she seemed genuinely interested in his thoughts.

For a moment, he was caught off guard.

”I’m thinking about what comes next,” Setsuna said, his gaze still fixed on the stars.

”This Singularity went pretty smoothly—we cleared it quickly and even brought three Heroic Spirits back with us. Definitely a big win.”

”But once we return, there’s going to be so much to do… First, I’ll need to review the magecraft data Dr. Roman’s been compiling and figure out how to incorporate it. Then, there’s the matter of integrating the three Heroic Spirits into the base…”

”Hmm, I wonder how far Akashi and her team have gotten with the spaceship construction. If all goes well, you guys should be able to start converting into starships soon…”

”Strike Freedom could probably use some tech upgrades too…”

”And then, there’s summoning more Heroic Spirits to consider…”

He rambled on, the words flowing effortlessly.

Ever since the base’s development had entered a stable phase, it felt like there was an endless list of tasks waiting for him every day.

His schedule was packed from morning till night.

Still, watching the base grow stronger, filled with more and more people, gave him a deep sense of satisfaction.

”Hmm…”

Taihou listened quietly as Setsuna enthusiastically laid out his grand plans for the future.

When he finally finished, she spoke softly:

”Whatever the Commander wishes to do, Taihou will always be by your side.”

”Even if it’s reaching for the stars, if you desire them, Taihou will bring them to you.”

”...”

Setsuna turned his head to look at her.

It is often said that when someone is in love, their eyes sparkle with light. At this moment, Taihou’s eyes seemed to hold the brilliance of a starry sky.

She gazed at him with a fiery intensity, filled with passion and warmth.

When she quieted down, she was an exceptionally alluring and beautiful girl.

”Commander, will you stay by my side too?”

”Mm.”

”Do you find Taihou clingy or annoying?…”

”Of course not.”

Setsuna shook his head.

Taihou’s behavior was occasionally a bit excessive, but there was no way he could ever truly dislike her.

”You don’t think I’m too greedy? You won’t get tired of me?”

”You’re not just putting on a front to indulge me while secretly being unable to stand it?…”

”Was what you said in the cockpit… true?…”

Taihou threw out a flurry of questions, looking at him cautiously.

Beneath her seemingly assertive exterior, she harbored her own insecurities and tender thoughts.

”...”

”I hope that one day you’ll become my Oathbound Ship.”

Setsuna paused, then answered seriously.

”Commander!!”

She flung herself into his arms, and he caught her effortlessly.

Without her rigging manifested, Taihou wasn’t heavy, given his current level of physical strength.

Carrying her, he began walking toward the bedroom.

”Taihou has been waiting for the Commander for a long time, and now there’s finally a chance…”

With a light tug, the short kimono she wore slipped open effortlessly.

”Wait a second… That military uniform design from back then—was it you who came up with something like this?”

Setsuna’s eyes widened in shock.

He suddenly recalled how Richelieu had spent half a day criticizing that particular uniform design. To think it had actually been Taihou’s creation all along.

”But of course,” Taihou replied with a hint of pride.

”My flight deck and enclosed hangar… aren’t they amazing? Are you… satisfied with them?”

She wrapped her arms around him, unabashedly displaying herself with confidence.

”I couldn’t possibly be more satisfied.”

Setsuna felt a surge of strength coursing through him, as though a bugle had sounded a call to charge.

For a fleeting moment, his mind drifted back to that afternoon years ago, when his teacher had asked him about his life goals:

”I want to join the navy and board an aircraft carrier!”