A giant robot.

Seeing such a thing, once thought to exist only in fantasy, up close was an awe-inspiring experience. Even on Earth, I’d never witnessed anything like this.

On Earth, where fantastical concepts didn’t exist, giant robots were often dismissed as impractical delusions. And indeed, they were.

There was no record of super robots ever being deployed for military use, nor of any wealthy individual building one for fun. On Earth, robots existed solely as two-dimensional constructs within fiction.

“Amazing... Does this really move on its own?”
“...To tell you the truth, it doesn’t actually move yet.”
“What? What do you mean—?”

For a moment, I was taken aback, but the researcher only gave a wry smile.

“It’s easier to show you. Would you like to see for yourself?”

With that, the researcher manipulated a few controls, and the robot, which was connected to various devices, started to move.

However, as soon as it took a step forward, something went wrong, and it began to topple.

It didn’t fall thanks to the array of devices attached to it, which kept it upright, but it certainly wasn’t because the robot could balance itself.

“Now you understand why we’re asking for a soul.”
“...You intend to teach it to walk?”
“Yes, exactly.”

The super robot before me couldn’t walk on its own. And that wasn’t surprising. Walking is an incredibly complex motion; after all, it takes humans over a year to master walking on two legs.

Just imagine the amount of computation required to make a giant machine walk. They wanted to use a soul to bridge that gap.

By giving the robot a sense of self and allowing it to learn the act of walking, it could eventually move on its own.

However...

“In that case, wouldn’t AI be a better solution? Why me instead of Dr. Kuroi?”

“We did contact Dr. Kuroi. But he admitted that he couldn’t replicate his previous results... In fact, he recommended you instead.”

“He recommended me?”

“Yes. Initially, we considered inviting Dr. Shira, who’s an expert in soul research. But she, too, suggested reaching out to you.”

So that’s why I, and not Dr. Kuroi, the AI expert, or Dr. Shira, the leading author on soul research, had been summoned. Apparently, there had been discussions I wasn’t even aware of behind the scenes.

I didn’t feel annoyed, though. Quite the opposite—I was relieved. It meant I wouldn’t have to hand this electrifying research over to anyone else.

I was thrilled.

“Alright.”

I reached out towards the giant robot and spoke.

“I’ll give that robot a soul, just as you desire.”

When it comes to creating something, the most crucial aspect is the design philosophy. While some inventions, like Viagra, might end up serving a different purpose than originally intended, usually there’s a clear purpose behind any creation.

So, what was the design philosophy of this robot? That was the key.

“Oh, you’d be better off asking the developer about that.”
“The developer? Isn’t this all the work of the research team?”
“We’re more like research assistants. The whole project is managed by one person...”

The researcher led me to the heart of the robot, where a man, his face smudged with soot, was tinkering with a wrench. He looked like a chimney sweep from 19th-century London.

“—Mr. Steelstone?”
“Mm?”
“This is our new research assistant.”

Steelstone stood up carefully. He was a small man, his body surprisingly large compared to his short stature. He wasn’t overweight; rather, he had a stout frame, almost like a character straight out of a fantasy novel—perhaps a dwarf.

“Research assistant? What kind of research?”
“A soul.”
“A soul? What does my robot need a soul for?”
“Well, it can’t walk on its own... So the higher-ups urgently requested—”
“Those damn fools. Manual control is way cooler. What’s the big deal about being a little slow?”

Steelstone grumbled as he wiped the grease off his massive hands and extended one toward me. His hand was as large as a cauldron lid. We shook hands, and he gave me a wide grin as he introduced himself.

“I’m Steelstone. Sorry for the mess. I’m like this pretty much 24/7, so I hope you understand.”
“Of course. I’m Dr. Eight, from City E.”
“Hmm...? City E, you say...?”

I expected him to bring up the giant robot incident, but instead, he brought up something completely unexpected.

“Oh, that’s where Cream Band is.”
“Cream Band...?”
“Don’t you know? They’re pretty famous. You know, that singing villain?”

I had a hunch. I nodded cautiously. In a city run by a villainous organization, a singing villain could only mean one person.

Former violinist Milka Pocato.
The girl who abandoned her violin for a guitar and embraced rock. I hadn’t expected her to be called Cream.

“She sings for those being exploited by corporations and governments. For some reason, listening to her songs seems to stir rebellion among people, so the authorities have been trying to ban her music...”

“Villains don’t care about bans.”

“Exactly! That’s what makes her the best. Do you know her? Can you bring her here? This city’s a barren wasteland when it comes to entertainment.”

I shrugged and promised to see what I could do. Revealing that I knew her might have led to immediate pestering to bring her here.

But right now, Cream Band was the last thing on my mind. The giant robot was far more important. I needed to know why they’d built it.

“Mr. Steelstone? I have a question.”
“What is it?”
“This robot. Why was it built? I mean—what’s it meant to do?”

At that, Steelstone’s gaze turned fierce, and he glared at the researcher who had led me here. The researcher gave a slight nod and replied.

“Security measures are in place.”
“Is that so? Then I suppose it’s alright to tell him?”
“Well... he might still be a blabbermouth willing to risk his life for secrecy, but yes, it should be fine.”

Steelstone looked me over, sizing me up, and after a moment, he deemed me trustworthy enough to speak.

“It’s a doomsday weapon.”
“...A doomsday weapon?”
“Yes. In other words, the folks in this city want to build a weapon that could take on every other city and win.”

Hearing that, Vira, who was standing behind me, let out a gasp. She glanced around, her eyes wide with disbelief.

I took a moment to examine the robot, evaluating its specifications. Could it, as Steelstone claimed, take on all the cities aside from City P and come out victorious...?

‘Well... with a few caveats, it might be possible.’

Naturally, if every hero and villain from all the cities aside from City P banded together against this robot, its goal wouldn’t be achievable.

I could devise a plan to counter the robot if I put my full strength into it.

However, considering a more realistic scenario—villains getting in heroes’ way, the world not seeing the robot as an immediate threat, the absence of other hidden doomsday weapons, and assuming our villainous organization didn’t get involved—under those conditions, it was plausible.

In that case, it was akin to having the only nuclear bomb on Earth. One nuclear bomb couldn’t win a war against the world, but it could tip the scales and possibly lead to world domination if played right.

“This is fascinating!”
“Right? You get it!”
“Yes! I’d love to lend a hand in this project.”

A doomsday weapon powerful enough to make enemies of the world. And if a soul were to be born within that weapon, the archetype was clear from history.

─The heroic figure who despises violence.

‘A doomsday weapon, huh...’

I beamed as I considered the soul I’d bestow upon the robot. Should I go with a classic hero archetype? Or perhaps a pure-hearted girl who’d become a weapon?

Just imagining the expressions on their faces once the soul and robot were complete sent a chill down my spine.

I was genuinely glad I’d taken on this task.