Countermeasures

"Two worlds…"

Ria stopped Serge as he muttered that.

"Wait, Serge. I don't understand what you mean by dimensional boundary."

"Ah, it's like a sci-fi thing. A wall that separates one world from another…"

Even Serge only understood it on a vague, intuitive level.

"Basically…"

In poor manners, Haruto spilled a few drops of tea onto the table.

"According to Valis, the world has a massive, thick root. Or perhaps you could call it a trunk."

He drew a thick line with spilled tea.

"Thin branches extend from it. Many, many of them. Eventually, they collide with each other. And then one—or both—shatter. That is the Great Collapse."

The tangled thin lines merged into one partway through.

"Using the power of the Soul Cycle to change the branches' course so they don't collide. That's probably what we should think of as the Millennium."

And then Haruto said something even more shocking.

"By the way, the Millennium doesn't happen once every thousand years. Wars between demons and humans occurred on other continents whenever a crisis arose. As a result, there are now virtually no humans or demons left on the other continents."

"That means…"

"That's right, the next Millennium will happen in less than a thousand years. Did you know that survivors from other continents came to this continent twelve hundred years ago? Apparently, they were survivors from when another system was used for the Soul Cycle."

This was terrible. Without the cycle of souls, the world would perish.

"Then how did we survive the Great Collapse three thousand years ago? I heard ten thousand humans came over from the other world…"

"Apparently, the previous Fire Divine Dragon destroyed the other world at the cost of her life. The humans that came to this world at that time—until then, the Millennium had been overcome through conflicts among demons."

Amazing, Divine Dragon-sama.

Wait, but then…

"The one who will prevent the next Great Collapse… is that going to be Valis?"

Having been told so much by Valis, Ria immediately realized it.

"That's right. We'll have her destroy the other world with her power, and at that time, we'll relocate the residents of that world to the other continents of this world. That should allow us to get through the Millennium for a while."

And then Haruto declared, "That's all I have to say."

While Serge summarized things for the three who didn't understand Japanese, Ria was lost in thought.

And she thought—wasn't this too arrogant? The arrogance of destroying another world.

In response, Haruto only asked her to come up with an alternative.

An alternative couldn't be so easily devised. This was something Haruto had thought up over a thousand years.

And the others felt the same way.

The carrying capacity of the three continents was estimated at a minimum of 600 million total. That was roughly the same as the current human population of the Dragon Bone Continent.

What kind of world would contact them in the next Great Collapse? Perhaps there would only be creatures that couldn't adapt to this world. Or perhaps there would be no intelligent life at all.

But what Haruto considered to be the problem was something completely different.

Namely, what if the humans of that world were far stronger than those of this one?

"But that's what the dragons are for, right?"

The sight she had seen at Valis's dwelling. Compared to a single dragon, no matter how many strong humans there were, they would be a dime a dozen.

But.

There was a but.

Gathered here were humans who surpassed even those dragons.

For enemies that dragons couldn't handle, humans—and the weapons humans had created—existed.

Indeed, at this point, there was no choice but to cooperate.

Haruto firmly grasped the hand Ria extended to him.

"By the way, why did the demons come south during the Millennium?"

From what she'd heard so far, there shouldn't have been a need to fight humans in this Millennium.

Haruto smiled wryly at her question.

"Well, the biggest issue is population. The Demonlands can't support any more demons. Population control policies don't work well."

A simple enough explanation.

"Also, I wanted to spread the Demonlands' advanced technology to the human world. What I initially thought was—couldn't humans and demons coexist?"

"Has demon technology really advanced that far?"

"Enough to build robots. Want me to show you?"

When shown one in the courtyard, Serge was extremely excited.

"You have enough mana to pilot it, so I don't mind giving you one."

It was just a verbal promise, but it was decided that Serge would receive a Machine God. How generous, Demon King-sama.

And finally, the conversation turned to how this war would end.

The demons didn't particularly want to rule over humans. They simply wanted enough territory to live on.

And even if that overlapped with human territory, there wasn't any particular problem with it.

On the other hand, humans didn't tolerate the existence of demons. This was due to feral demons and the atrocities of the Millennium a thousand years ago, but they couldn't just give up and accept it.

"By the way, those humans who were sent to the Demonlands seem to be adapting."

Haruto mentioned that as well.

"The only option is for the demons to win, but not too overwhelmingly, and gain territory…"

Listening to the opinions of civil officials like Guinevere and Fio, Ria pondered.

"From among those with aptitude, I'd like to scout some as our pilots."

It seemed a unit had already been prepared for Ferna.

"What about me and Carla?"

"Wouldn't you two be stronger fighting as you are?"

The truth was that Haruto didn't want to create forces outside his control, but the two of them accepted that explanation.

Regarding Casalia, Ria's connections might be able to work something out. The problem was the other countries.

Lemdria was especially problematic. A vast territory. Powerful soldiers. Enormous national strength. It could probably be called the strongest nation on this continent now. A country that surpassed even Ogress and Casalia.

"If we defeat them, won't the other countries naturally fall in line?"

That's what Ria thought, but Guinevere considered it more politically.

"There's no way they could just surrender to demons. The citizens wouldn't accept it."

Is that so? Ria, the queen of Ogress, was bewildered. In the case of Ogress, having beastkin and the ogres that gave the country its name reduced resistance.

Through Ria's blood ties, things might work out between Casalia and the demons. But what about Lemdria?

They maintained a powerful monarchy and had a formidable army. And a large population. Subjugating them certainly wouldn't be easy.

"Come to think of it, how much time do we have until the Great Collapse?"

Ria and the others had completely forgotten to ask about that.

"The more people and demons that die, the longer the reprieve—unfortunately."

Given the Soul Cycle, that made sense. It was certainly frustrating.

"In the end, there's no option but for the demons to overwhelmingly defeat the humans and then negotiate a peace treaty?"

"Exactly. And the one playing the mediator at that time will be Ogress."

That was Haruto's conclusion. Everyone else agreed.

"By the way…"

With a ferocious smile different from before, Ria fixed her gaze on Haruto.

"Would you care to have a match with me?"

"No way. What if something went wrong?"

"We have someone who can use resurrection magic right here."

Ria gestured toward Carla with her palm. But Haruto shook his head.

"Once we're in the Millennium, resurrection magic becomes unusable."

The Soul Cycle would become too intense—even Valis couldn't resurrect the dead, he said.

If they weren't completely dead, something could be done, but if they had truly died, there was nothing that could be done even immediately after death.

"So be careful, everyone."

Haruto said it lightly.

"Well then, I suppose we should head back."

Since their discussion was over, that was only natural, but Guinevere and the others tried to somehow keep him from leaving.

This led to a catfight with Ferna, but that's a digression.