“Oh! It’s actually starting?!”
“So you finally debuted as an exploration streamer, Tooru-bro!”
“M’lady’s with him too.”
“Came here from M’lady’s stream.”
“Here from the M’lady’s SNS.”
“I pre-subscribed to the channel, Tooru-bro!”
“Tia-tan! Tia-tan! Uoooooh! Tia-tan is the strongest!”

“Uh… wow. There are a ton of people watching. Seriously?”

When he checked the stream on his mobile terminal, the screen showed himself and Tia standing at the entrance to the Sugai Dungeon, staring down at the device, while Kujou Reiko posed smugly for the camera with a triumphant grin.

Viewer count: 22,000.

Just the other day, his average live stream viewership had been zero.

So this was what it meant to go viral—Tooru let out a wry chuckle. If things worked like this, then people who were earnestly grinding away day after day really didn’t get rewarded fairly.

That said, it wasn’t like he planned to hold himself back out of guilt and live apologetically for their sake.

“O-ho-ho-ho! Welcome, dear viewers! You are most graciously gathered here on Toorubro-sama’s channel! I am your guest today, Kujou Reiko! Do remember me well!”

Laughing loudly, Kujou Reiko started talking before anyone else could, but neither Tooru nor Tia felt particularly inclined to comment on that fact.

“What even is this?”
“If you didn’t come from M’lady’s stream, this makes zero sense lol.”
“Tooru-bro, explain already.”

“Uh… yeah. So, Kujou Reiko-san showed up and said she’d teach me about dungeon exploration. We’re heading into the Sugai Dungeon—it’s the one that had a Dungeon Stampede just yesterday. Apparently, Kujou-san got permission from the Dungeon Agency under the pretext that she, as an A-rank explorer, would investigate it. She suggested doing the exploration as a stream on my channel. The one holding the streaming camera right now is her butler. …That about right?”

“Every single detail is correct!”

Kujou Reiko’s voice was unnecessarily loud, as usual.

She hadn’t even done anything yet, but she already seemed to be having the time of her life—maybe this was just her normal operating mode.

“For real, it’s literally the next day.”
“The Sugai Dungeon branch office is still wrecked, right?”
“No deaths at the branch office, though, yeah?”
“There wasn’t any footage from inside Sugai—what kind of monsters came out?”

There were so many comments flying by that just skimming through them and picking which ones to answer felt like it would take some serious practice.

Watching Anthem’s streams or Kujou Reiko’s streams had felt completely detached, so following the comments had been easy. Doing it on his own stream, though, somehow felt way harder.

“Uh… sorry, but I don’t really know the details either. Yesterday, after I cut down that big thing in the Noumi Dungeon, I went home, ate dinner, took a bath, and went to sleep. As for the Dungeon Stampede, I guess we’ll have to wait for an official announcement. Anyway, let’s head in. I know the route down to the fourth floor, so if things look different from what I remember, that’ll mean there’s been a dungeon mutation. As for questions, I figure that holy sword user over there can answer them as we go.”

Saying that, Tooru tossed his spare mobile terminal—used to check comments—over to Tia.

“Is it okay if I chat with the commenters? Then I’ll tell them all sorts of things. Ah—Tooru, Tooru! They’re calling me cute!”

“Yeah, yeah, sure. Cute, cute.”

“Now then, let us begin our dungeon attack, everyone! O-ho-ho-ho!”

“…This is supposed to be an investigation, you know.”

He already felt tired before even setting foot on the first basement floor, but—well.

Thus began Tooru’s very first dungeon exploration stream as an explorer.

◇◇◇

Tooru had hunted trash monsters as a cleaner from the first basement floor of the Sugai Dungeon down to the fourth. Having wandered that area nonstop for three full years, the exploration up until the descent to the fifth floor felt like it was being fast-forwarded.

And as it turned out, there were no problems.

Along the way, there had been a moment where he absentmindedly clubbed a demigoblin or a giant rat to death and muttered something like, “Demigob three,” toward a body camera he wasn’t even wearing, earning a round of laughter from the viewers—but aside from that, there had been no noticeable changes in the Sugai Dungeon up through the fourth floor.

Just to be safe, he had also stopped by the spot where that strange illusionary wall had once been, but the wall was now just an ordinary wall. There was no hidden passage, no ringing in his ears, and no specter in hakama to be seen.

He wondered, briefly, what that whole thing had ultimately been about—but since thinking about it wasn’t likely to produce an answer, Tooru decided to cut that train of thought short for now.

Starting from the fifth basement floor, discrepancies began to appear in the information about the monsters that spawned.

The Sugai Dungeon, designated as D-rank, was an absolute trash-tier area up through the upper floors—up to the fourth floor, only bottom-of-the-barrel fodder monsters appeared, the kind even sub-D-rank cleaners could handle. There were no traps, no mid-bosses—just a worthless stretch of dungeon.

That didn’t change much even in the mid-layer, from the fifth to the tenth floor. Monsters that even D-rank beginner explorers could easily defeat—though they’d still be dangerous for ordinary civilians—started roaming around. From the eleventh to the fifteenth floors, monsters that were “rough for beginners” began to appear. Supposedly. For reference, the deepest part of the Sugai Dungeon was the sixteenth basement floor, which served as the boss room.

To put it simply, the dungeon had changed.

Not in its structure—but in the monsters that appeared.

“Oh my? How strange. A pack of Gray Dogs. According to the records, they were supposed to be lower-layer monsters in the Sugai Dungeon.”

Kujou Reiko tilted her head curiously as she gazed at the pack of red-eyed wolves that had appeared down the corridor. Her tone was more that’s not where that stray cat’s territory should be than anything else—there wasn’t a shred of tension in it.

Which was only natural—so natural it hardly needed saying.

Kujou Reiko was an A-rank explorer, and the monsters before them were high-tier D-rank.

“It would seem the dungeon truly has undergone some changes. Jouichirou? You have been recording all of the monsters that have appeared thus far, yes?”

“’Course I have, M’lady,” the butler replied in an utterly unmotivated voice as he continued filming Tooru and the others with the streaming camera.

“Hey, Tooru. We didn’t actually look over any materials on the Sugai Dungeon, did we?”

“We didn’t—and honestly, I don’t even really know what the investigation’s supposed to cover. We’re checking the map as we go, so even if things have changed, I’ve got no clue what’s different.”

“Blunt honesty, lol.”
“Well, can’t really help it.”
“Tooru-bro, since you’re being blunt—I’ll back you up. That’s basically all you can do. Check whether the existing maps match the dungeon you’re actually traversing, whether the monsters match the documented data, and if there are notes in the materials, see whether reality lines up with those. That’s about it.”

“Oh hey, we’ve got an expert. Go on, be friendly.”

“That’s not a very nice way to put it, Tooru. But still, let’s say thank you. Thanks for the info!”

Tia smiled brightly and waved at the camera as she spoke. Come to think of it, she was still dressed like an ordinary town girl, holding the Holy Sword Lightbringer in her hands. Apparently, that was more than enough.

Unlike during the Anthem incident, this wasn’t a job where she had to protect a noble young lady. If anything, Kujou Reiko seemed far more eager to lead them.

“Ohohoho! You two! While you’re busy with that, they are getting awfully close, you know? But since we have this fine opportunity, allow me—Kujou Reiko—to show you just a glimpse of my true ability!”

The moment she finished speaking in her characteristically booming voice, knuckle guard-equipped Kujou Reiko’s figure slid away—meaning, she closed the distance to the pack of dogs.

Whether it was footwork or stepping technique, her movement clearly had form to it—something born of training and refinement.

She closed in in an instant and delivered a body hook to the nearest Gray Dog—if the opponent had been human.

Since it was a dog, its head burst apart with a pop.

A sharp whoosh of motion, then pop!

That sequence repeated several times, and in the blink of an eye, the entire pack of Gray Dogs was wiped out. Soon after, the monsters’ bodies began to disintegrate into particles—the sign of death—leaving behind their magic cores on the ground.

“Wew! As expected of M’lady!”
“When it’s fodder enemies, her clean movement really stands out!”
“As expected of ‘Kujou Play.’”

“Ohhh, that was decently impressive. You’ve trained quite a bit, haven’t you?”

“I am most honored by your praise!”

Faced with Tia’s casually condescending compliment, Kujou Reiko showed not the slightest hint of irritation. If anything, she returned with a beaming smile.

And so, without even thinking about it, Tooru found himself picking up the abandoned magic cores and tossing them into his magic bag.

It was a completely unconscious action.

“……”

“……”

“……”

“Shut up. Don’t say it. Don’t say anything. …Wait, you didn’t say anything…”

“Veteran movement, lol.”
“Three years of cleaner experience shining through.”
“Looks like you trained pretty hard too, Tooru-bro.”

It got a laugh out of the viewers, but he hadn’t been trying to make a joke. And judging by how natural that had felt, it probably wasn’t a habit he’d break anytime soon.

Not that Tooru had any intention of fixing it in the first place.

“Uh… anyway, Kujou-san, the way you move—it felt like some kind of martial art. Like there’s a proper form, and you’re applying it directly to real combat… I’m not exactly an expert, though.”

“Oho, sharp eye, bro.”
“Didn’t you say to Kagurazaka Chizuru you never even held a sword?”
“They call it ‘Kujou Play,’ Tooru-bro. Remember that.”
“Also, this is bro’s channel, you know.”
“You guys better subscribe while you’re at it.”

“To be perfectly honest, I purchased the DVDs online! Apparently, the founder has decreed that one should not use the art’s name for profit. So, out of respect, perhaps I shall refer to it as Kujou-style Fist Way. Ohohohoho!”

After laughing to her heart’s content, Kujou Reiko lightly brushed beneath her nose with the pad of her thumb, then snapped into a sharp stance.

A blonde, drill-haired young lady in a day dress, wearing knuckle guards and striking one of those Fist of Fury poses should have looked ridiculous from an objective standpoint—but her posture was far too beautiful for mockery. Instead, it inspired genuine admiration.

It was a stance with a perfectly centered core, as though an iron rod ran straight through the middle of her body—solid, unwavering, and utterly composed in both posture and movement.

“It’s probably a martial art that excels at controlling the flow of power. The way it moves mana through each action seems especially compatible with mana circulation. The fact that the gauntlets don’t cover the fingertips means it likely incorporates hand techniques, not just punches. And that footwork—skimming just above the ground—was really impressive!”

Tia nodded enthusiastically as she shared her impressions. As expected, her depth of combat experience was on another level—her eye for observation was keen.

The chat comments quickly filled with expressions of surprise and admiration for Tia’s insight, and she laughed happily as she started chatting back and forth with the viewers.

In any case, standing around wasn’t accomplishing anything, so they resumed moving on.

As they descended through the seventh, eighth, and ninth basement floors, the rank of the monsters they encountered clearly increased with each level. The dungeon corridors themselves still matched the existing maps perfectly, yet only the types of monsters had changed—an oddly unsettling inconsistency.

From time to time, Tooru also had to deal with monsters using his reinforced rebar club, but even when facing multiple mid-tier C-rank Evil Monkeys at once, he handled them without the slightest hint of danger.

“Tooru-bro’s really handling this effortlessly.”
“Hard to believe he was a sub-D-rank cleaner until recently.”
“This can’t just be the holy sword’s blessing or whatever.”
“That thing’s a blunt weapon made from bundled rebar welded together, right? Why does that even work on monsters?”

“Uh… yeah, good question. Now that you mention it. I mean, if they’re weak mobs, sure, you hit them with a blunt weapon and they die—but monkeys like those should normally just bounce it off, right?”

“Even he doesn’t know, lol.”
“Would M’lady or the butler know?”

“Ohohohoho! You have called upon my name, have you not? Very well—I, Kujou Reiko, shall enlighten you! Toorubro-sama, are you aware of why we even use swords and spears instead of guns against monsters?”

Tooru hadn’t actually called her name, but he decided against making a tactless correction. After all, this was supposed to be a learning opportunity.

“Uh… I think I heard about this back in middle school, during dungeon exploration class. Attacks without mana don’t really work on monsters.”

“Exactly! Excellently put, Toorubro-sama! Attacks devoid of mana cannot pierce mana-based defenses! And if that is so, then the answer is already before us! A sword strike infused with mana by an explorer far surpasses the power of bullets fired by a soldier with no mana at all! In other words—Toorubro-sama—you, too, are imbuing your attacks with mana!”

“Oh… huh. Is that how it works?”

He found himself genuinely impressed.

“Were you truly unaware of this?”

“Yeah. Mostly.”

“That, in itself, is rather alarming. From the time you were still below D-rank, Toorubro-sama, you have been fighting day after day… then a dragon, a black knight, dungeon exploration with Anthem, and then slaying two large-scale monsters that appeared due to the Dungeon Stampede. No matter how low your mana affinity may have been, you should have leveled up quite significantly by now.”

“Oh, that makes sense.”
“True—there’s no way a sub-D-rank cleaner would normally gain that much experience.”
“So it ended up being insane power leveling, huh.”

“Under normal circumstances, one would be completely bewildered by such a drastic change in one’s physical abilities. Yet from my perspective, Toorubro-sama, the flow of your mana and your movements hardly seem like those of someone fighting without a defined style.”

“Good to know.”

Tooru nodded vaguely and cut the conversation short—but only then did it finally click why his body moved so naturally, exactly the way he wanted it to.

Still, he decided it wasn’t something worth broadcasting to the world. The idea that the cursed sword Kagetsu, which existed by feeding on his very soul, was almost automatically updating how his body moved to match his level as he grew stronger.

It was true that Tooru moved his body by his own will and swung his reinforced rebar club to smash monsters—but those movements were possible because Kagetsu was installing them directly into his body. Without any conscious effort, the cursed blade’s effects made his body respond like that of a seasoned master.

A cursed tool that’s basically a lump of combat experience.

That was how Tia had once described it. And thinking about it now, Tooru realized that maybe he’d been cursed by the blade right from the very beginning.

What made him laugh was that he didn’t actually resent it.

A man who had once been nothing more than a sub-D-rank cleaner was now walking through a dungeon alongside an A-rank explorer, all because he’d been a little cursed.

What a ridiculous story.

It really did feel unfair to the people who were earnestly grinding away day after day.

At the very least, he should make sure not to get carried away, Tooru thought.

Not that he ever intended to in the first place.