―――The palace in Yuritania, the capital of the Yuri Empire.

In a rather small conference room on the second floor, a group of important people was gathered.

Altorius, the Holy King of the Holy Land of Nimun and Pope of the Church of the Eight Gods, Cadain Theodore, the monarch of the Duchy of Selsia, and Raven Rapier, the king of the Kingdom of Rapier: the kings of the three countries were seated in the conference room, with a few guards standing behind them.

Of course, Yuri, the Empress of the Yuri Empire, is also seated in one of the seats.

Next to Yuri, a woman in a maid’s uniform―――Partita, the captain of <Nadeshiko>, a unit that specializes in espionage, quickly got things underway.

“As a result of our investigation, we found out that the ‘Mud Wolf’ that has been spotted near the border of the Volmisian Empire is due to a dungeon in its country.”

“.... “Labyrinth Dungeon”?”

“No, Master. It’s not like the “Labyrinth” in the cities of Ulysses and Eureka, but the ‘dungeons’ that originally existed in this world.”

“Ah, I see..”

Come to think of it―――I remember hearing from Altorius a few times before that dungeons exist in this world.

“To distinguish them from the “Labyrinth” in our country, the ones in the Volmisian Empire will henceforth be referred to as ‘natural dungeons’.

This natural dungeon is said to be a ‘demon’s nest’ with a large number of high-level demons compared to the demons that live on the surface.”

“Hmmm.. I don’t know much about these ‘natural dungeons’ since they don’t exist within the country. Are there any in the territories of the Holy Land of Nimun, the Principality of Selsia, or the Kingdom of Rapier?”

“It’s not in my country.”

“It’s not known to exist here either.”

“I’ve never heard of such a thing.”

At Yuri’s question, the kings of the three countries each shook their heads.

If the lord of four countries is gathered here, but none of them has a natural dungeon. The ‘natural dungeons’ of this world are few and far between and must be quite valuable.

“I had no idea that it was a dungeon monster.. But it makes sense now that you mention it. In a way, it is natural for these demons to be highly threatening.”

“That’s true.”

Although the demons that exist on the surface of the Duchy of Selsia are generally within the range of 15 to 30 levels. The level of the ‘Mud Wolf’ that was confirmed in this case was 56, which is outstandingly high.

However, it makes sense when you think that it’s a demon that came out of a natural dungeon, as Cadain said. As natural dungeons are ‘habitats for high-level individuals,’ it is natural that there are demons with high levels.

“I’m sure you’re not familiar with it, so let me explain about natural dungeons themselves first. ―――To put it simply, natural dungeons are places with their own set of rules that are different from the demons that exist on the surface.”

“.... Own rules?”

“Yes. As you all know, the demons on the surface of the earth have a rule that the number of inhabitants is generally constant. Even if we reduce the number of demons by actively hunting them, as we do in our ‘extermination’ program, it will not be a fundamental solution because all the demons that we have defeated will be resurrected as soon as the moon cross.

This is also true in reverse. If you don’t hunt demons, it won’t lead to an increase in the number of demons.”

“.. Oh, really?”

“Yes. For example, lizardmen and other demons that live only in lakes and marshes are often left unhunted. This does not increase their numbers, they say.”

“I see..”

Until now, Yuri had thought that the demons of this world only had the characteristic of coming back every month. So I thought that if you didn’t hunt, the population would naturally increase through breeding―――but it seems that’s not the case.

The number of demons in this world is neither increasing nor decreasing. Demons can’t seek the prosperity of their species, but they can never be eliminated.

―――Then it seems that the way of life that should have existed as a living thing is not recognized by these “demons”.

I see――― If it is only defined to exist. It could rightly be called ‘rule-governed’.

“However, a completely different set of rules apply to the demons that live in natural dungeons.

―――First of all, there is no concept of ‘moon’. It’s not just a matter of time, but it’s also a matter of how long it takes to recover.

“Always..?”

“Yes. It might be easier to say, ‘The population increases by a certain number every day.’ So if you annihilate the demons living in a natural dungeon, it will take quite a while for the population to recover. Even if the moon cross in the middle of the month, it will not bring the population back altogether.

And the reverse is also true for this. The rule of ‘keep a constant number’ that exists for surface monsters does not apply to natural dungeon monsters, so there is no limit to the recovery of the population. If you don’t hunt the monsters in natural dungeons, the population that lives in them will continue to grow day by day.”

“And the result―――it’s overflowing.. is that it?”

“You guessed it. Basically, demons in natural dungeons don’t seem to leak out of their habitats, but when they become overgrown, it’s a different story.

The natural dungeon where the Mud Wolves live is located near the city of Homarid, west of the capital of the Volmisian Empire. It was a dungeon similar to a natural cave, and the dungeon was filled with mud wolves―――It was clear just by looking at it that it was already flooded.”

“I see..”

Of course, natural dungeons have their capacity for tolerance.

If the number of demons increases too much, there is no other choice but to drive them out. And since it’s already flooded, the number of demons that ‘increase by a certain number every day’ will be expelled from the natural dungeon as it is.

In the past, when the Yuri Empire made the Duchy of Selsia a vassal state, the Volmisian Empire, known for its vicious behavior, did not interfere at all with either the Yuri Empire or the Duchy of Selsia, and this was of no small concern. But―――

There’s nothing to say. At that point, the Volmisian Empire was already overflowing with mud wolves. It’s probably because of the damage they’ve done to merchants and villages that they weren’t in a position to interfere in other countries.

“What is the current situation in the Volmisian Empire?”

“I don’t know if they were wiped out by the Mud Wolves or if they evacuated voluntarily, but it seems that most of the villages that once existed in his country are now abandoned.

Fortunately, the mud wolf is quite fast in running speed, but not so in jumping power. If a city has sufficient walls, it is possible to protect it, and there seems to be no damage inside the city. However, it seems that the cities whose walls were not solid enough were easily destroyed and fell.”

“What a mess..”

It’s not hard to imagine how big a threat this demon is, just because it’s a huge wolf. The average soldier or adventurer in this world would not be able to compete with them.

Of course, from the point of view of the Yuri Empire, it is no threat at all.

If it is a level 56 demon, even the children of the <Water Lily>, who have the least fighting ability, can easily slaughter it with their bare hands while laughing. Of course, this is true even if the demon is practically the equivalent of a level 65 demon.

The easiest way to help the Volmisian Empire would be through the Yuri Empire.

Nevertheless―――

(I don’t have any obligation to help them.)

We have no diplomatic relations with the Volmisian Empire. We have no acquaintance with the other country’s lord, nobles, or wealthy people, and we have nothing to do with this country on a private level.

In the meantime, the land was ceded after the peace with the Duchy of Selsia. ―――The mountainous area where the mining city of Eureka and the “Shinto City” under construction are located is close to the Volmisian Empire, and this country and the Yuri Empire share a small border, but that’s all.

Yuri didn’t have any reason to actively help them.