Grimm's face was a skull, making his expression impossible to read.
Even so, perhaps because Rei had known him for a fair amount of time, the Grimm displayed in the Paired Orbs looked somehow tired.
Rei could vaguely guess the reason for that exhaustion, and it was precisely why he felt the possibility of Grimm being involved in the current Treant Forest incident had grown stronger.
"Hmm. Do you have some business with me? I am currently rather busy, you see."
"Busy—is that because of the Eyeball's material?"
"Umu. That material has quite interesting properties. Right now, I am investigating whether it possesses any other special characteristics."
"I figured."
What Grimm had obtained was the material from the giant eyeball monster.
Nor was it a mere eyeball—countless tentacles sprouted around its circumference, and it even had a tail behind it that closely resembled an optic nerve.
It was a monster that existed in a space outside this world, capable of tearing open spatial rifts to interfere with this one. It could even create or summon vast numbers of monsters through living sacrifices.
Whether to call it a blessing in disguise or not, the Red Cloth members had served as the sacrifices in Rei's case. Perhaps because they were low-quality offerings, the resulting monsters had only been Cobolts.
If a High-Rank Adventurer or an Alias Holder had been offered up instead, what manner of monster might have been summoned?
The thought alone made Rei feel a renewed wariness toward that Eyeball.
"In any case, that's not why I'm calling... well, it's not that it doesn't matter, but I contacted you because I wanted to ask something related to it. I tried reaching you yesterday and the day before, but couldn't get through at all."
"I see. I was somewhat absorbed in my research. So, what business brings you to contact me? Regarding the Eyeball's material, much remains under investigation, so there is little I can share."
"No, that's not it. ...Not that I'm uninterested."
The moment Rei said it wasn't that, Grimm visibly drooped with disappointment, and Rei hurriedly clarified that he was indeed interested.
Whether Grimm believed him or had simply been acting disappointed was impossible to tell, but he raised his head and spoke regardless.
"I see. Then we shall discuss that later... So, what is it you wish to know?"
"Actually, for the past few days, Green People—whose skin, hair, and even blood are green—along with Lizardmen hostile to them, have been teleporting into the Treant Forest near Gilm. That Eyeball also had abilities that interfered with space, so I wondered if this might be happening as a result of some experiment of yours."
"..."
Grimm fell silent for a few seconds at Rei's words.
Rei couldn't tell what that silence meant, but he pressed on regardless.
"So? How about it? Does anything come to mind?"
"Hmm. Unfortunately, I have no recollection of anything of the sort. At present, I am not conducting any experiments that would produce effects in that area."
"At present" likely meant that at some point in the future, he did intend to run such experiments.
Still, as long as it didn't cause Rei any trouble, he had no intention of objecting.
"Then am I correct to understand that you've had nothing to do with the Green People and Lizardmen teleporting in over the past several days?"
"Umu, that is correct. ...However, Green People?"
Grimm puzzled over Rei's words—the term "Green People" and the explanation of what kind of beings they were.
It wasn't just Rei who showed surprise at Grimm's reaction in the Paired Orbs; Elena and the others were equally astonished.
Given that Grimm possessed power worthy of the title Lich Lord, having lived since the era when Zephyle was still alive—or rather, "existed," since he was Undead—Rei had assumed there was virtually nothing in this world that Grimm didn't know.
(So my gut feeling was right after all—they came from another world? Well, it's not as if Grimm necessarily knows everything about other continents, though.)
Rei studied Grimm's demeanor and spoke.
"Hey, Grimm. Have you ever heard of the Green People?"
"Umu. I have not. What is certain is that they are not a race native to this continent."
"...Not this continent, but a race that doesn't exist in this world?"
The moment Rei said that, Grimm froze for an instant and fixed him with a sharp gaze.
Strictly speaking, Grimm had no eyeballs, but even through the Paired Orbs, the intensity of that stare was unmistakable.
"! ...S-so? Do you think that's possible?"
Though Grimm's gaze made him catch his breath, Rei pressed on without flinching.
Grimm, on the other side of the Paired Orbs, held that gaze steadily... for several seconds, perhaps more than ten.
After that long silence, he finally spoke.
"I would not say the possibility is nonexistent. As evidenced by Rei's own arrival in this world, the method of crossing over from another world is not impossible."
Rei nodded with an expression that said he'd expected as much.
In contrast, the three women wore matching expressions of surprise.
"Is that... truly the case?"
Elena asked Grimm, almost involuntarily.
The other two didn't voice it, but wore similar looks.
Even knowing of Rei's existence, the notion that beings could cross from another world into this one wasn't so easily believed.
"Since I have not seen them directly, I cannot say with certainty."
"The Green People aside, there were Lizardmen as well... do Lizardmen exist in other worlds too?"
It was Marina who voiced the next question, following Elena's lead.
The idea that the same monsters as this world existed in someplace called another world seemed hard to accept.
Of course, since Zozo and his kind possessed enough intelligence to form a nation, they couldn't exactly be called the same as this world's Lizardmen.
"It is not impossible, I suppose. That said... Rei. In the world you originally came from, did Lizardmen exist?"
"No, they didn't. Let alone that—Elves, Dwarves, and Beastmen don't exist either, and there's absolutely nothing like magic. ...Well, maybe magic did exist, but at the very least, I never encountered any."
"Hoh."
That the differences were that pronounced was apparently unexpected, and Grimm let out a sound of genuine interest.
Unlike Grimm, Elena, Marina, and Vihera didn't show particular surprise. All three had occasionally heard stories about Rei's original world from him.
That said, when they first heard those stories, they had been quite astonished themselves.
"No Lizardmen in Rei's world, hm... But worlds exist in countless numbers. If so, it would not be strange for a world to exist where Lizardmen do as well."
Parallel worlds. Alternate realities. Such terms surfaced in Rei's mind.
For example, a world where Rei ate bread for breakfast, and a world where he ate Yaki Udon.
Countless worlds branching off in that manner...
(No, another world and a parallel world are fundamentally different concepts, aren't they?)
The thought came unbidden.
It was strictly Rei's knowledge—gleaned from manga, anime, games, and novels he had consumed while in Japan, not anything academic. But even so, he understood the distinction between another world and a parallel world.
"In any case, I came here through reincarnation... no, possession? Teleportation? It's hard to explain exactly, but going off something close to the intuition I developed from experiencing it myself, it really does feel like the Lizardmen came from another world."
"Hmm. I cannot cite a clear reason, but it does seem to come down to that... Interesting. A sixth sense unique to Rei, one might say."
"Being amused by it doesn't help... In any case. This situation with the Lizardmen isn't your doing, Grimm—it's definitely not the result of some experiment, right?"
Sensing the conversation veering in an odd direction, Rei pressed for confirmation one final time.
"Umu. I am investigating the Eyeball's material and running light experiments, but it has not produced anything like what you are worried about. ...That said, it is the first time I have obtained such material, so I cannot completely deny the possibility of some unknown side effect occurring without my awareness."
There didn't appear to be any lie in Grimm's words.
To an outsider, trusting an Undead to such a degree might seem questionable, and understandably so.
But to Rei, Grimm was undeniably someone he could rely on. After all, Grimm had saved him time and time again.
"I see. ...Then for now, I'll assume this incident has nothing to do with the material you took."
"Rei, why don't you ask him about that matter?"
As Rei looked disappointed at the lost lead, Elena suddenly spoke up.
Since Rei was juggling any number of issues, "that matter" was enough for him to understand.
"About what?"
"The language barrier. We can only teach them words painstakingly, one at a time..."
Elena paused there and turned her gaze toward Grimm's image in the Paired Orbs.
They couldn't resolve it themselves, but Grimm might be able to do something about it.
Her meaning was clear.
Rei understood Elena's intent, gave a small nod, and addressed Grimm through the Paired Orbs.
"Hey, Grimm. About the Green People and Lizardmen who teleported here—they can't understand our language at all. Communication is all gestures and body language. We've been teaching them a few basic words, but... we have no idea when they'll actually be able to understand us."
"Hoh. Not just the Lizardmen, but the Green People can't understand language either?"
"That's right. I'm fairly sure both races speak the same language among themselves, but..."
Since they couldn't communicate, it wasn't guaranteed that the Green People and Lizardmen shared a common tongue.
However, as someone who frequently interacted with both races, Rei was fairly confident they did.
...The fact that the Green People and Lizardmen appeared to communicate with each other was also a strong indicator.
"Hmm. ...Wait a moment."
With that, Grimm's figure vanished from the Paired Orbs.
Rei guessed he had gone to search for something.
That meant there was a good chance Grimm possessed something capable of changing the current situation—something that would allow them to understand the Green People's and Lizardmen's language.
(If I'd known that, I would have tried contacting Grimm sooner... no, wait. Never mind. Whether I'd called yesterday or the day before, Grimm would've been absorbed in his research regardless.)
He had actually tried reaching Grimm through the Paired Orbs and failed to connect, so his reasoning was sound.
"Looks like things will work out somehow," Marina said.
The others nodded in agreement.
Even though it was obvious that Zozo followed Rei, the language barrier still caused all sorts of problems.
That was why having Grimm prepare some kind of Magic Item was an enormous help.
"So, what kind of item do you think it'll be? I'm guessing a Magic Item of some sort."
"That's almost certainly correct. The real question is what kind of Magic Item, wouldn't you say?"
"Hmm... a bracelet?"
Vihera offered in response to Marina, but Rei shook his head.
"If it's something that lets the wearer speak, wouldn't it need to be near the mouth? That'd mean a necklace, a piercing, a collar... something along those lines, right?"
"Incorrect."
The voice that denied Rei's guess came from Grimm, who had reappeared in the Paired Orbs.
In his hands, he held a stone tablet roughly the size one would need both arms to carry.
"That?"
"Umu. Some time ago—perhaps a hundred years or so. A Magic Item I found in a Dungeon I delved around that time. It senses the user's intent and displays it as text on the surface of this stone tablet. Originally, it was used by someone who could not speak..."
I see.
Rei nodded, genuinely convinced by Grimm's words.