Returning home, Jin left matters in Kaina Village to Butler A and took the Warp Gate in his workshop basement back to Hourai Island.
"Laojun, give me the details."
Jin skipped the pleasantries and got straight to the point.
『Certainly. It began with...』
Laojun provided a chronological explanation.
It started when Lishia happened to greet Earl Walter while in the Town of Rakham and spent the night at his villa.
There was a high probability that the communication pigeons used at the time had been tampered with. The reasoning was that the birds showed signs of illness, such as ruffled feathers, shortly afterward.
Lishia’s condition had already begun to deteriorate by the day she left Toka Village. Then, the day after she fell ill, Earl Walter followed suit.
Finally, just this morning, the Count’s condition took a sudden turn for the worse until he...
"That Count... he was nothing but trouble right to the bitter end."
Listening to the report, Jin clenched his fists so tightly his nails dug into his palms. He felt a surge of white-hot anger toward Earl Walter, but his target was already gone from this world.
Jin forced himself to shift his focus to the most pressing priority: countermeasures.
"I see. My deduction matches yours, Laojun. This is likely a contagious plague transmitted via birds."
The terms avian influenza and psittacosis crossed Jin’s mind. A similar disease evidently existed in this world as well.
『When Lishia-san fell ill, she made a full recovery thanks to our recovery medicine. As I reported at the time, her belongings were sterilized with ultraviolet light and other methods, and medicine was administered to both the horses and the pigeons.』
Furthermore, to be safe, Jin had recently seen to it that all the villagers drank Persica juice imbued with medicinal properties. For now, Kaina Village could be considered safe.
"But the villages along Lishia’s route, not to mention the Town of Rakham and the surrounding area..."
This was exactly what Jin had feared. So far, no other patients had been reported.
However, if the disease could spread from humans back to birds as well as birds to humans, it would be a catastrophe. It would sweep across the entire Klein Kingdom and into neighboring nations in an instant. It would be a full-blown pandemic.
『We have already recovered the dagger belonging to that suspected demon—the man calling himself Laldus—to pinpoint his location. Land Y should be delivering it shortly.』
"Hm? Land Y? What’s he doing with it?"
Land Y was supposed to be part of the Kaina Village defense force. Jin wondered why he was carrying a demon’s possession.
『Yes. Deneb 30 was tracking Laldus, but he spotted her, leading to a brief skirmish. While she managed to seize his dagger, Deneb 30 also suffered an attack that caused her to malfunction. Therefore, I dispatched Land Y and Land Z as support. Land Y was tasked with securing the dagger, while Land Z was sent to recover Deneb 30.』
"Sending Deneb 30 to track him alone was a mistake on my part."
『No, the fault is mine. I prioritized minimizing the chance of detection, as more units would have increased that risk, but the decision backfired. Furthermore, since they were heading into the Great Shama Marshland, there were no suitable Quinta units nearby.』
"I suppose that couldn't be helped... Well, as long as we haven't lost track of this Laldus fellow, we'll call it a success."
『Indeed. According to the report from Koushin, no one is following Land Y. We can safely assume the demon race is not in pursuit.』
As if on cue, Land Y returned via Kaina Village. It went without saying that, per Laojun's instructions, he had raised his body temperature to 200 degrees Celsius during the journey for sterilization.
"Good work, Land Y."
"Master, you’ve returned. Laojun, here is the dagger in question."
Land Y attempted to hand the dagger to Laozi, who was acting as Laojun's terminal. Jin interjected before he could.
"Wait, let me see that."
Jin took the dagger and his eyes widened. He didn't recognize the material.
For there to be a substance unknown to Jin, a Magi Craft Meister, was a rare thing indeed.
"...I suspect it’s a biological material."
Jin set his curiosity aside for the moment and handed the weapon to Laozi. Locating Laldus was the priority. Laozi placed the dagger into Laojun's analysis terminal.
『The magic pattern is quite faint, but it is sufficient. I have recorded it. Commencing tracking now.』
Following that announcement, Laojun activated the magi-radar. A few minutes later, he spoke again.
『I have found him. A significant magic reaction matching Laldus is currently entering the Leonard Kingdom.』
"The Leonard Kingdom, huh..."
Though it was part of the Allied Kingdoms, a massive, unbroken mountain range isolated it from its neighbors, leaving its true nature a mystery.
The Quinta had not yet been dispatched to that region.
"I want to deploy Quinta units to the Shouro Empire and the Leonard Kingdom as well. We’ll need to increase their numbers."
『My Lord, are you ordering a mass production of the Quinta?』
When Jin confirmed, Laojun voiced a concern.
『My Lord, considering Laldus's physical capabilities, I am uneasy about relying on the current Quinta models alone.』
Jin nodded; the point was valid. As he began to consider specific upgrades, Deneb 30 arrived, carried by Land Z.
Naturally, they had also undergone heat sterilization before entering Kaina Village. They had not been followed.
"Good work, Deneb 30, Land Z."
As Jin addressed them, Land Z replied simply.
"I have merely fulfilled my duty. If you'll excuse me."
He returned to Kaina Village immediately, but Deneb 30 looked toward Jin with a regretful expression.
"Chief, I am terribly sorry. I have damaged the body you gave me."
Jin spoke gently to her.
"It's fine. You did well. Without the information you gathered, this situation could have been much worse."
"You are too kind, sir."
Jin stopped Deneb 30 as she tried to bow.
"We don't have much time. Give me a detailed report."
While he had received a summary from Laojun, Jin wanted to hear the facts directly from the one who had faced Laldus.
"Yes, sir. He was..."
As Deneb 30 gave her oral report, Jin set about repairing her.
This was where a Magi Craft Meister truly excelled.
He worked on the magical skin, magical muscle, and the skeletal structure of her right arm where the dagger had slashed through.
Everything was mended using Craft Magic. The cuts were exceptionally clean, which spoke to the terrifying sharpness of the demon's blade.
Once finished, he performed a full diagnostic and refurbished every worn component he found.
He handed the replaced magi-recorder over to Laojun for analysis and swapped her magi-crystal for a fresh one. With that, Deneb 30 was back to full operational status.
"...That concludes my report. Chief, thank you for the repairs."
Jin nodded as Deneb 30 bowed.
"...Understood. He certainly doesn't sound human. Anne, what do you think?"
Laojun had already summoned Anne, who possessed firsthand knowledge of the Great Magic War.
"He is undoubtedly a member of the demon race. Their physical capabilities are several to dozens of times that of a human, so it is only natural that Deneb 30 struggled. His incantations are also characteristic of the demons."
Anne confirmed Jin's suspicions.
"I doubt a demon of that caliber could have survived an Ether Stampede, so I suspect he was born after the war," she added.
Her speculation offered little comfort.
"I see. But that doesn't help us much right now. You mentioned he used something like Master-Slave magic?"
"Yes, using Elradrite."
"I'm glad we implemented those countermeasures..."
Robust protections against Master-Slave Rewrite Magic had been installed in every golem and automata on Hourai Island. Jin shuddered to think what would have happened if he had been lax with those designs.
Since the principles were likely the same, Deneb 30 had been immune to the demon's attempt at enslavement.
The magi-crystal from the recorder should have both the Master-Slave magic and the attack magic stored within.
While he awaited the analysis, Jin shifted his focus back to the immediate crisis.
"I'm concerned about him and whether there are other demons, but I'll leave that to the new Quinta units. Right now, the plague takes precedence."
Anne spoke up again, offering a surprising lead.
"A plague? I believe I recall a similar situation occurring during the Great Magic War."
"What?! Are you sure?"
The diary found in the ruins had mentioned chemical weapons like strong acid. It wasn't a stretch to imagine biological weapons existed as well.
"I am sorry, but my memories of that period are fragmented. I cannot provide the details."
If it was a matter from the Great Magic War, there might be records in the control core of the former Golden Destruction Princess—Elena. Laojun was already managing that data.
It seemed Laojun had finished the search before Jin could even ask, as he immediately stated the conclusion.
『The disease used by the demon race is known as 'Magical Consumption Fever.' It is transmitted from birds to humans and from humans to humans. It has an incubation period of two to five days. It causes a high fever and intense pain, followed by severe debilitation and eventually death. The mortality rate is approximately 70 percent. Depending on the individual's constitution, some may not develop symptoms at all. That is the extent of our information.』
A 70 percent mortality rate was a terrifying threat. The only relief was that it didn't seem to spread from humans back to birds.
"Do we have an effective cure?"
『Unfortunately, no.』
Jin fell into a deep silence. In Lishia’s case, recovery medicine had worked, but there was no telling how many people would eventually fall ill. Did they have enough medicine for everyone? And even if they did, how would they distribute it?
"Warp Gates and airplanes won't be enough."
Those were point-to-point transport methods. This required a strategy that covered entire regions.
"We need to catch that demon and get the details from him."
Even as they prepared the medicine, they needed as much information as possible.
"Laojun, can you keep a lock on his location?"
『Yes.』
"In that case, the person best suited for this is..."
Jin glanced to his side.
Standing there in silent, loyal poise was Jin’s finest creation. Reiko.
She understood his gaze instantly.
"Yes, Father. Leave it to me. I will capture this demon Laldus and make him surrender everything he knows about the disease."
"...I'm sorry, Reiko. I told you I'd treat you more like a girl, yet the ink on that promise hasn't even dried and I'm asking this of you. I'm a poor father."
Reiko shook her head.
"No, Father. I am an automata. To be of use to my creator and father is my greatest joy."
Jin stroked her head, his voice still heavy with regret.
"Can I count on you? You have my permission to use Pegasus 1 if needed. Once you're off, I'll speak with Lishia and Pascoe and arrange for them to coordinate with the Klein Kingdom."
Jin decided it would be more efficient to have them move in their official capacity as nobles.
"I understand. I will coordinate my actions with Laojun."
"There's no one else I can trust with this. Good luck."
With that, Reiko set out to capture Laldus the Jest.
Meanwhile, Jin stood his ground, preparing to save the people of the Klein Kingdom.
"Reiko, if things get dangerous, don't hesitate to use your full power."
Those final words were the mark of his grim resolve.