Er, I'll give you a brief history of the current situation.
　I was set up by Mendale, a former mayor and modern official.

　At first, you see, I was going to take advantage of my position as an advisor and wait for Mr. Hasty while eating and sleeping in the guest house. But as soon as we arrived at the guesthouse, Mr. Mendale came in....

"You came at a good time, Advisor Ryota-dono!　In fact, we have operated a part of the completed sewage purification system for the first time, but its performance has fallen far short of our expectations. It is not likely to be able to purify the swamp itself, as it will only be used for sewage treatment. We have hired some water magicians, but we don't have the budget to do it...

　At this time, in an inopportune moment, I allowed the former thinking crystal Yukikaze to materialize, and I mumbled, [I think Tanishi and Shijimi could be used for water purification].

　Usually it's a telekinetic story, so only I can hear it, but since it was unusually materialized, Yukikaze inadvertently said it aloud. And although it was a very low voice, Representative Mendale didn't miss it.

　He then immediately rushed to the Alp Mercenary Xina Branch and forcibly appointed a request to capture Tanishi and Shijimi under the name of Acting Dragon Council. The branch manager hurriedly searched for Tanishi and Shijimi's demons, found and approved the demonic beast called Demon Core Tanishi, and approved it.

　And even though I had plenty of funds, I couldn't say no, so I had to do the job.

　Moreover, this Demon Core Tanishi is classified as a demonic beast, but its body is small and harmless. The tip of its shell is a little bit hexenucleated, so it's scientifically called a Hexenbiest. Still, a demonic beast is a demonic beast, and if someone pays for it, it can be used as an extermination request.


The swamp in the demon area near Xina

I didn't know this shellfish was a demon. I've never heard of this kind of thing before.

　It's a good thing that even ordinary gardenias are able to purify the water, but the demon nucleus of the Alp Mercenary's Kishina Branch's demon catalogue showed that the demon nucleus is extremely high in purification ability.

I've confirmed that it's because of the demon nucleus that it's considered a demon monster by scholars. They are edible monsters, but they taste bad, and they can't be used as fuel because they can't be separated from their shells. But there were requests to exterminate them a long time ago.

　In case you're wondering, I looked up since the old extermination. The reason for this is that a terrifying firefly insect demon called [Biting Firefly] used this Demon Nucleus Tanishi as its staple food in its larval stage. It's safer and cheaper to exterminate the demon core snails and larvae than to defeat the main body.

　But how much of a demon could a firefly be so terrifying?　But then I remembered that it was a ferocious image. There are actually tanks and fighters named Firefly (Firefly).

　As a millionaire, I'm embarrassed that I didn't realize the origin of the name, as I know it. Putting that aside, to counteract this 【Biting Firefly】, in the past, it wasn't uncommon to receive requests to exterminate the Demon Nuclear Tanishi.

　In fact, it is said that this actually led to a decrease in the number of [Biting Fireflies] and reduced the damage to humans and livestock. However, about a thousand years ago, the [Biting Fireflies] began to be over-hunted, and on the verge of extinction, the requests themselves disappeared.

　I was curious about the reason why this [Biting Firefly] was on the verge of extinction, so I looked into it. What a safe method of capturing and incapacitating them was established, and it was due to their market value soaring as a cheap light source.

　This demon firefly, if it's meat, it eats anything, whether it's insects or goblins, so it's very cheap to maintain. The quantity of light is as high as the headlights of a car, and if a few of them are used to adjust the interval of light emission, there is no problem as a light source, and the demand for them was enormous in the nighttime transportation industry and nighttime fishing.

　And unlike ordinary fireflies, you can catch them all year round. All you have to do is cut off their wings, legs, and jaws, and tie them to a stick for safety. It's a firefly, but since it's a demon, it has a long life span of four months. Still, since it was a consumable item, the demand was maintained and they were hunted even without a request.

　It was said to have generated so much wealth that it was called an exterminator's diamond.

　However, they took too many stones and are now on the verge of extinction. It is no longer able to generate masses of strength and has now dropped to a very weak demon. They are currently protected in a very small part of the south, but it seems that poaching is constant because they are traded for high prices in the back market for maniacs.

　Looking at the data, the human race is much crueler and more fearsome than the others.

　Well, on the contrary, the Demon Nucleus Tanishi increased too much with the absence of natural enemies, and there was no problem at all with capturing them. However, it was a 30cm long giant Tanishi, and capturing it was very hard on my back.

'Sorry Lord. The records of the old Ares civilization show that they used shells to cleanse the polluted water, so I was just wondering...

　Note that Yukikaze is playing jumbo shijimi catcher with Mogu. The cycle of Mogu sneakily transferring the mud in the area where the shijimi clam is likely to be located to the basket, and Yukikaze uses the swamp water to remove the mud.

'The reward is moderate, but the danger is small. It's not a bad job, so I don't mind.

　The Demon Nucleus Tani is one large copper, and the Jumbo Shijimi is two large copper coins for a tubful of clams. The unit price is small, but we can capture a lot of them safely and easily. So the subsistence rate isn't bad, we simply didn't want to do the work.

　By the way, since Pina is on alert in the air, there's no need to worry about being ambushed by other demons.

''Ryota-sama, ordinary tanishes are going to be foodstuffs for the north too, right?　There is no need to have a thick magnesium pool like in the sewage swamp or the bewitching area, and there is no need to worry about parasites if the fish is thoroughly cooked with a farmable protein source. I will disinfect it after the work is done.

　If there is an aquatic demon, it is exterminated with a remote-controlled gun rack (RWS) 7.62mm machine gun. Since it is a shallow swamp, the water refraction can be compensated and the bullets can reach the bottom of the swamp. However, save your ammo by chasing them off with grenades.

(The Demon Nucleus Tanishi is fully defended by covering its shell, and the Shijimi is in the mud, so no damage is done.)