The beginning was last winter.

It was said to be around the time that the highest-difficulty labyrinth had begun to be conquered.

In the southern country, there exists a group of ruins known as the Prehistoric Great Ruins.

They are the remnants of an ancient civilization destroyed by the Ruin King. Unlike labyrinths that naturally form from the stagnation of magical power, these are artificial structures, yet they are said to possess a complexity that may even surpass the highest-difficulty labyrinths. To the people of the current civilization, they are unexplored territories.

A mage who had set up his base near these ruins detected signs of an anomaly.

The southern jungle spreads around the Great Ruins. The mage, who was researching plant-related magic there, noticed the recurring phenomenon of "tremors" in his daily life.

Bottles lined up on the shelves would rattle.

Ripples would form in the coffee poured into a beaker.

At first, he attributed it to the wind or perhaps the aging structure of his research laboratory—nothing more than minor explanations.

However, as he conducted fieldwork around the ruins, he began to suspect that he might have been making a hasty assumption. The "tremors" existed outside the laboratory as well, and in some cases, they felt even stronger.

The mage took out measuring instruments and began keeping detailed records.

The time the tremors were recorded. Their intensity. Their location. He compiled the data into various graphs and maps for analysis.

Three things became clear as a result.

First, the frequency of the "tremors" was abnormally high.

Second, the intensity of the tremors tended to increase the deeper one went into the jungle.

And third, both the frequency and the magnitude were growing stronger by the day...

Coincidentally, the time when the mage became convinced of this and submitted his report to the Magic Federation was just after the Ruin King had been resealed. The peculiar nature of the "Great Ruins," where the tremors were occurring, led the Federation to hypothesize a connection between the two.

In other words.

These "tremors" might also be related to some phenomenon connected to the Ruin King.

However, with the sudden outbreak of magical beast disasters occurring across various regions after the resealing, the Magic Federation was too preoccupied with handling them to launch an investigation immediately.

Several months passed, and finally.

Finally, they had gathered the personnel necessary for the investigation.

The three who played key roles in the Ruin King’s resealing—the swordsman, the cleric, and the mage.

Along with them, the swordsman’s apprentice, an adventurer who had uncovered the secrets of the Apocryphal Demon Armament in the eastern country. The mage’s mentor, the Vice Director of the Grand Library, who possessed knowledge of prehistoric civilizations.

In other words, they were the ones who would undertake this mission.

"So, that means us, huh?"

"That’s how I understood it."

"Ah, that’s right. I’m relieved to see that Klaha has conveyed it well."

The room, which initially held three people, had now become five.

The midsummer sunlight streamed into the room. The ones originally there were Ziel, Lililia, and Eunice.

The newcomers were Klaha and Wilae.

And naturally, it was Klaha who had just explained the situation, having summarized everything she had learned from Wilae.

"I see. That makes sense. ...Just to confirm, I’m not really expected to contribute much as an investigator, am I?"

"Of course not. What we’re asking of you is to serve as a bodyguard for us mages."

"Figured as much," Ziel nodded, leaning lightly against the window frame.

He had been informed that this involved the Ruin King.

And from the moment he heard that, or rather, from the moment he skimmed through the header of Eunice’s request letter, he had anticipated that combat would be involved.

Wielding a sword was the only thing he could do.

He often said it himself, but it was simply the truth.

So, for a brief moment, as he listened to Klaha's explanation, he felt a flicker of unease—Would he also have to decipher something? Take measurements?—but when it became clear that wasn’t the case, he could focus on what he was good at.

That was perfectly fine.

However...

"...Are you sure about this?"

Something nagged at him.

"Hmm? What do you mean?"

"Eunice, and especially Lililia. You both seemed busy, and being here—"

He hesitated, just a little.

Was it really his place to say this?

But then, he recalled the face of his rival, whom he had crossed swords with and honed his skills against until just the other day.

"Isn’t it dangerous to gather all of us here? There aren’t that many people capable of holding the front line when Apocryphal Beasts appear, are there?"

He voiced his concern based on a straightforward assessment of combat capability.

Deploying three individuals who could single-handedly deal with Apocryphal Beasts—was that really the right move?

Eunice nodded in understanding.

"You’re absolutely right. In fact, that was the reason we couldn’t go to your aid back in the spring, Ziel. I truly regret that."

"No, that’s not a problem... Ah."

Rather, he recalled something.

They had already discussed this thoroughly through letters once things had settled down, but he felt he should say it face-to-face at least once.

"Both of you, you really helped me back then. Thanks to you, I was able to handle the Thirteen Gate Oni, the Gate Beast, and even the Apocryphal Magic Mirror. I truly appreciate it."

"Oh, come now. That was the least we could do. You can rely on us anytime—we’re friends, after all."

"Hearing that helps. Lililia, you too—"

He was about to thank her when he noticed her expression.

She looked deep in thought, her face serious.

"Something wrong?"

"Ah, no. I was just considering the order..."

"Order? Of what?"

"The order of things to discuss... Alright, let’s start with this."

With that, Lililia reached into her pocket and pulled out a thin thread.

"The response to the magical beast disasters has settled down for now, so we’re fine. We can return immediately if anything happens, but we’ve already established a mass production system for the Net."

"Wait, what?"

Ziel couldn’t help but let out a strange noise.

Because he recognized it.

"That’s what Master had..."

"Yes. When he used this in the eastern country to defeat the Thirteen Gate Oni, the various national governments began actively funding its production."

The Net.

A magical detection tool for tracking magical beasts, one that Valdfried had received from a cleric during his travels.

Ziel had experienced firsthand just how incredibly useful it was—both during their journey together and in the decisive battle in the eastern town.

"And with the help of the grandmothers—the Three Saints—they established diplomatic channels and managed to get an international treaty signed. Now, whenever an Apocryphal Beast appears, national security forces, the church, the Magic Federation, and the Adventurers’ Guild will all work together in defense."

"Lililia anticipated this and, while managing the church headquarters, also worked on organizing the mass production of the Net and sanctuary talismans, right?"

"...Where did you hear that, Eunice?"

"A little bird told me."

'Amazing', Ziel thought

Ziel was impressed.

While he had been facing the Apocryphal Beast, Lililia had managed to turn the situation around on a larger scale. Even Eunice, in between subjugating the beast, had been using hints from the magic mirror to develop new magic.

At the same time he thought, I can’t afford to fall behind, he also felt a genuine sense of admiration.

“For now, as long as we have the Net and the Sanctuary Talisman, everything won’t suddenly collapse all at once. So, Ziel-kun, until you’re summoned, you can relax and continue investigating here without worry. …Now then,”

And from there—

Lililia stood up.

Up until just moments ago, the people in the room had been arranged like this: since there were only three chairs, Ziel had declined first, saying, “I’m fine,” and naturally, Klaha stood beside him. Just as they were about to start a cycle of polite refusals, Wilae intervened, saying, “I’ll take you up on that offer. You two as well, you must be tired,” and settled the matter.

As a result, Ziel stood beside Klaha while listening to her explanation, with Lililia, Eunice, and Wilae surrounding them in a fan-like formation.

So, when Lililia stood up, it meant—she was heading toward them.

“Sir Ziel. Lady Klaha.”

“Huh?”

The formal address, the serious tone, and her expression—

“The other day, you both went to great lengths to subjugate the Apocryphal Beasts, Thirteen-Gate Oni and Beast of the Gate, which appeared in the Eastern lands, as well as to destroy the Apocryphal Magic Mirror.

Though we have already expressed our gratitude through the local church, since we have been given another opportunity to meet like this, I would like to once again extend my deepest thanks on behalf of the church.”

Seeing her bow with such sincerity, it was clear that her words came from the heart.

Ziel, too—

“—Likewise. There were people and a town that could not have been saved without the church’s assistance. I sincerely thank you once again.”

“Thank you very much.”

A strong feeling welled up—he had to respond with equal sincerity.

Ziel bowed his head alongside Klaha.

Slowly, they raised their heads again.

When their eyes met, Lililia smiled a little awkwardly.

“…By the way, Eunice didn’t like this approach.”

“It feels kind of distant, doesn’t it? Ziel, what do you think?”

Ziel couldn’t deny Eunice’s point and smiled wryly.

But imagining himself in Lililia’s position—though the thought itself felt presumptuous—he could understand the desire to properly acknowledge such moments.

“Either way. If it happens, I’ll respond, and it makes me feel respected, which is nice. If it doesn’t, it just feels like trust… or familiarity.”

“You always try to balance things out, don’t you, Ziel?”

“Even when you were hanging in midair earlier, you were surprisingly easy to hold.”

“That has nothing to do with this,” Ziel laughed.

Lililia and Eunice also chuckled.

“—Well then,”

Wilae stood up.

“It seems the initial explanations have been conveyed, so let’s conclude this for now. Once again, Ziel-san, Klaha-san, thank you for cooperating with this investigation as part of the Magic Federation. We’ll be working as a team for the time being, so I look forward to it.”

“No, the pleasure is ours.” “Looking forward to working together.”

They exchanged slight bows.

“We plan to start tomorrow morning. It won’t be a full-scale operation just yet, but more of a light orientation to help everyone understand the path ahead. Since you must be tired from traveling, I’d recommend getting some rest early. …Though, for Ziel-san, who’s accustomed to traveling, and Klaha-san, the adventurer, this advice may not be necessary—but especially for Lililia and Eunice.”

She gestured toward the two.

Ziel suddenly recalled something he hadn’t asked yet.

“Did you two arrive here pretty early?”

“No, just today. I was working until the last minute… and honestly, I’m incredibly sleepy right now.”

“I also arrived around noon. I could fall asleep at any moment.”

“And despite that, you still had the energy for those pranks…”

“It’s like a separate reserve.” “It’s fun while you’re doing it.”

Seeing their eyelids grow heavy as they spoke, Ziel nudged them, “Go to sleep. It’s bad for your health.”

“Yeah…” “Okay…”

They obediently accepted the advice.

So, Wilae said,

“I’ll escort these two to their rooms. Otherwise, they might collapse in the hallway.”

“Teacher. We’re not children…”

“That’s rich coming from someone who was sleeping at a desk just recently, Eunice. If Ziel-san and Klaha-san have the energy afterward, I can introduce you to the rest of the team. How about it?”

“The rest of the team?”

Ziel tilted his head, and Klaha suddenly spoke up beside him.

“Ah, my apologies, I forgot to mention. In addition to the five of us, there will be three more participants: the mage who reported the matter, their assistant, and an external collaborator who is a friend.”

“Oh, no worries. Thanks for letting me know.”

“Klaha, how about you? Are you tired from traveling…? That’s a bad way to ask, isn’t it? Makes it hard to say if you are.”

“Ah, no! I’m completely fine today. In fact, since I haven’t had much exercise during the boat trip, I was hoping you could give me some additional training later.”

“Oh, sure. Absolutely. In that case, if we’re starting early tomorrow… I’d like to introduce myself to the others today.”

Klaha nodded.

Then, she turned to Wilae.

“If Eunice-san just arrived today, then you must also be tired, Wilae-san.”

“Ah, well. It wasn’t too much of a burden…”

“We’ve already received the building layout, so Ziel-san and I can handle the introductions on our own. If it’s alright, please take the chance to rest with them.”

Klaha spoke with a firm yet polite tone.

Ziel glanced at her, slightly impressed.

Wilae hesitated for a moment before nodding.

“Then, I’ll take you up on that offer. The three of them should be in the laboratory at the end of the first floor. Do you know where that is?”

“Yes. No problem.”

“Alright, then I’ll leave it to you. If you need anything, just come to the second floor’s private rooms.”

Ziel and Klaha nodded.

Wilae then turned to Eunice and Lililia, who looked ready to doze off at any moment.

“Alright, let’s at least stay awake until we reach your rooms.”

And as they prepared to leave—

“—Ziel.”

“Hm?”

Eunice turned around.

With a mysterious grin, he said—

“I’m really looking forward to tomorrow. Very much.”