Crossover Shipgirls: Building a Dimensional Empire from Scratch

”Bulin Engineering Squad No. 2 reporting in!”

Just ten minutes later, two squads of well-trained Bulins walked out from the teleportation anchor point, carrying tools.

There were purple ones, gold ones, rainbow-colored ones—all carrying wrenches and meow-meow hammers. They lined up neatly on the clearing and reported to Setsuna.

”Wow?!”

”You have this many little girls at home? Are they sisters or what? Why do they all look exactly the same?!”

Bumblebee was stunned at first, then carefully studied the Bulins.

From the outside, aside from the numbers on their chests, there were no differences at all.

”Dude, are you... cloning cute girls at home for fun?”

Wheeljack and Mirage gave Setsuna a look that was borderline gentlemanly.

They suspected Setsuna might be raising a harem of identical girls and doing all sorts of unspeakable things daily.

”You got this many? Do you even have the time for them, bro?”

Bumblebee patted Setsuna on the shoulder.

”...”

”Focus.”

Setsuna thought Bumblebee had quite the imagination, but he clearly knew nothing of the true might of the Eternal Snowfall.

The Bulins quickly lined up in front of the Autobots.

The rainbow Bulin in the lead stood in front of Optimus Prime, looked up, and sized him up. Prime extended a hand in greeting:

”Uh, hello?”

”Hyaa?!”

Rainbow Bulin hadn’t expected the giant robot to talk. She jumped in surprise.

”Commander, is this some kind of autonomous Gundam-rin?!”

”This is a Transformer—an alien mechanical lifeform in this world. They’re basically high-tech constructs. See if you can enhance them.”

Setsuna gestured casually.

He figured that since Transformers were pure tech-based constructs, they should fall under Bulin jurisdiction.

It all depended on whether the little ones could wrap their heads around Cybertronian anatomy.

”Buli.”

Rainbow Bulin knocked lightly on Optimus Prime’s foot and tilted her head thoughtfully.

”Commander, do you have their 070 schematics?”

”Uh, no. You’ll have to study them onsite. You can use the Decepticon parts for reference.”

Setsuna pulled out Megatron’s remains.

”...”

A group of rainbow Bulins crowded in, surrounding Setsuna and Prime.

Tap tap, poke poke, hammer hammer.

After a good ten minutes, they looked up.

”Bulin thinks it’s doable!”

”If you say so, then it’s a go. Begin work!”

”???”

The Autobots were dumbfounded by Setsuna and the Bulins’ blind confidence.

”Wait! Dude! I thought you guys already understood Cybertronians! You’re figuring this out now?!”

Bumblebee was horrified.

It felt like being on an operating table and watching your surgeon flipping through a textbook called Surgery: Volume I.

”Trust the Bulins. I’m a product of their upgrades too.”

”If they mess you up, I’ll compensate you with a spaceship.”

Setsuna patted Specialized Bulin on the head.

”...”

”Amazing...”

Bumblebee hesitated, then decided Setsuna probably wouldn’t harm him.

He obediently transformed into vehicle mode, ready to give it a try.

”A Gundam that turns into a car, burin?!”

The Bulins had never seen a Transformer before. They swarmed over the yellow Chevrolet.

”Tell them to be gentle, bro.”

Bumblebee honked twice at Setsuna.

He had a bad feeling about the wrenches and hammers in their hands.

”Bulin knows, burin.”

A crowd of Bulins quickly lifted him onto the clearing. They pulled out a mountain of materials from their riggings and started modifying on the spot.

”Wait wait wait—”

”Don’t pry open my hood! I’ll do it myself!!!”

”Hey! Hey! That’s my headlight!! Replacing it with a super-graviton cannon?! What does that even mean?!”

”Oh oh oh oh—what are you installing under my feet? Anti-gravity boosters?!...”

The Bulins dismantled and reassembled Bumblebee at blinding speed, leaving the other Autobots in awe.

”What the heck, those little girls are faster than Ratchet.”

”No, wait. Ratchet only does repairs. Modifications are usually Decepticon business.”

Mirage tapped his head in thought.

They had never seen such efficient modification work even on Cybertron. The Bulins didn’t rely on external machinery—they could perform precise high-end processing entirely on their own.

Even if their tools looked odd, their effectiveness was unquestionable.

”You guys come next.”

Setsuna motioned to Optimus, Arcee, Wheeljack, and the others who were spectating.

”Tell the Bulins whatever you want. Once we install anti-gravity, super-graviton cannons, and Klein Fields, you’ll be the most badass Transformers on all of Cybertron.”

”Oohhh—”

Led by Optimus Prime, a line of Transformers transformed into vehicle mode and were swarmed by Bulins, then carried into the forest.

There, in an energy-rich area, they were modified with a symphony of clanks and bangs.

The Autobots were nervous yet excited, eager for the Gundam-like upgrades Setsuna had described—capable of flying through space and burrowing through the earth.

But they were soon dumbfounded by the Bulins’ completely unorthodox approach to engineering.

”Hmm? Something doesn’t seem right here? Whatever, just whack it.”

”The super-graviton cannon looks misaligned. Meow-meow hammer! Pass me the meow-meow hammer.”

”This calls for a drill, purin!!”

”No, whack it with the wrench, buli!!!”

”...”

Bumblebee looked on in horror at the flurry of hammers, wrenches, and drills around him.

”Bro, are you sure they’re qualified for this?!”

...

Elsewhere—

While the Bulins were working on the Autobots, two Siren girls were busy studying how to modify the Decepticons.

They had set up a makeshift research station in the forest using a bunch of strange-looking equipment.

When Setsuna stopped by to take a look, Purifier and Observer were experimenting on Megatron with several mysterious devices.

”Commander, we discovered that Cybertronians have a very unique structure. They’re essentially silicon-based lifeforms that rely on energy to function.”

”It could be nuclear energy, solar, or anything else—Cybertronian bodies convert it into usable power, kind of like how humans eat food.”

Observer enthusiastically shared her findings with Setsuna.

This was her first encounter with true silicon-based lifeforms.

Most members of the base were carbon-based. As for Ikaros and Nymph, they looked so human-like that the Sirens usually just treated them as people.

”Did you discover anything else?”

Setsuna asked.

”Any special data from Megatron or the other Decepticons?”

”Of course, Commander. We can revive Megatron and make him work for you.”

Observer used a tentacle from her rigging to lift up a metal head.

It had a deep gash down the forehead—Megatron, who had previously been killed by Setsuna.

”Cybertronians are mechanical lifeforms, which means we can use certain technological methods to interfere with and control their thoughts and actions.”

”Like programming a robot with the Three Laws of Robotics—we can hard-code some absolute rules.”

”Huh?!”

Gudako and the watching shipgirls flinched.

Of course the Sirens would casually bring up mind control like it was no big deal.

But on second thought, it made sense. For carbon-based life, magic could be used for mental manipulation—like Mio or Tohru.

So for silicon-based lifeforms, technology was the obvious choice—a perfect fit for the Sirens’ expertise.

”So basically, make Megatron... a little more obedient?”

Setsuna mulled it over for a moment.

This guy could really fight—way better than the Autobots. The only issue was that the Decepticons loved racial supremacy and had the temperament of a berserker, picking fights with anyone they saw and bowing to no one.

”Mm, we can modify his thought processes to some extent, adding an obedience module like the ones used in enforcers.”

”For example: cannot attack creators, cannot initiate attacks on Autobots, and so on...”

Purifier nodded. The Sirens had made countless AI-driven sub-Siren enforcers and were well-versed in this kind of programming.

”In addition, if the Commander is interested, we could add some... creative tweaks.”

Observer spun Megatron’s head in her hand as she sat in her chair.

”Like inserting an experimental personality module to completely overwrite his original character.”

”Turning him into a bratty loli or a tsundere bot is also totally doable...”

”???”

Setsuna froze for a second.

Smack—!

He karate-chopped Observer’s head, making the little loli grimace in pain.

”Can you not be weird for once?!”

Siren Observer: power level unknown, technological genius, personality: awful.

Moral bottom line: likely in the negatives.

Installing a bratty loli personality module into a Transformer? Only this lunatic would come up with that.

Just imagining a twenty-meter-tall steel giant yelling at him, ”Trash~ Trash~ Commander-chan is trash~!”

”Optimus-chan is trash too~! All Autobots are trash~!”

Setsuna felt an overwhelming urge to gouge out his own eyes.

The other shipgirls smacked their foreheads—they were completely done with this unhinged Siren girl.

Megatron was, after all, the dignified leader of the Decepticons. Say what you will about his moral alignment, in terms of leadership and combat ability, he even edged out Optimus Prime.

But in the hands of the Sirens, his reputation might not survive.

”If you’re not into bratty types, Commander, I also have yandere and tsundere personality modules...”

Observer continued pitching her cursed ideas.

Bonk—!

She got smacked on the head again.

”Keep this up and I’ll turn you into a plush toy and lock you in the Eternal Snowfall’s dark room.”

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