"Taking on a request in the middle of a weekday… Ugh, what a pain in the butt."

It's been about 70 years since these fantasy-like dungeons started appearing all over the world. At least, that's what they taught us in World History A, which focuses on modern times. Honestly, I don't really get it. They should just make a separate class called Dungeon History or something. Not that it matters to me since I barely pay attention in class anyway.

Apparently, it's been about 70 years since humanity first started conquering dungeons. But for someone like me, who just explores dungeons to get by, it's all irrelevant… or at least, it should be. I might've learned something about it in a training seminar or whatever, but I was too shocked by how few people were actually paying attention to remember any of it.

"Good job out there!"

"Great work, as always!"

"You're amazing!"

As I emerge from the dungeon back to the surface, I'm greeted by a swarm of overly polite Dungeon Association staff. They seem a bit tense, though. I mean, come on, I'm just a high school student. They could be a little more casual with me. But if I told them that, they'd probably just freak out and apologize, so whatever.

I get it; they're public servants. It's part of the job.

"EX-Rank Explorer, UNKNOWN, returning!"

"…So embarrassing."

"Right this way, please. The branch manager is expecting you."

Ugh, it's so cringy. I should really change my registered name. Why did I submit it blank two years ago? And why do they insist on calling me by my explorer name? I'd much prefer if they just used my real name.

"Hey, hey! That was fast again, huh?"

"I just like to get work done quickly."

"We really appreciate it, Tsukasa Kisaragi."

"…Thanks."

As I enter the room, I'm greeted by a young man with a suspiciously friendly smile. He stands up immediately and offers me a handshake. I take it, but seriously, that forced business smile is more like a creepy stalker grin.

"I knew you were the right person for the job. All the other reliable explorers were busy, and if I sent in someone mediocre and they failed, it'd be on me."

"Yeah, sure. But calling a student out in the middle of a weekday like it's no big deal… Not cool, man."

"Don't worry about it. That's why you're enrolled in a private high school with a more flexible schedule, right?"

"Actually, I got my explorer license after I started high school."

Is this guy even listening to himself? At first, I thought he was just flattering me, but now it's clear he's just talking nonsense. And I'm not impressed. It's basically like having a high schooler do an adult's job. Even if I am an EX-rank explorer, there are limits, you know? I could sue this guy for exploiting me. No wonder they're always short-staffed.

Not that complaining in my head is going to solve the staffing issue. And this guy is just another cog in the machine of the Dungeon Association, probably struggling in his own way. Not that I trust his sketchy smile, though.

"I'll make sure the payment is transferred to your account, so rest easy."

"Thanks."

"Haha… With that much money, you could probably buy whatever you want, huh?"

"Maybe… Yeah, I guess so."

"You're so humble."

"If you think this is humble, you might want to see a doctor or visit the labor board."

The Dungeon Association really thinks money solves everything. They should be questioning the fact that they're making a high schooler work. Yeah, I agreed to it when I became EX-rank, but still.

Ugh… This is such a pain. I wish there was someone else who could take on my jobs, so I could just relax, go to school, and sleep soundly at home. Can't a new EX-rank explorer just show up already?

Since dungeons started appearing around the world, human life has supposedly changed drastically. Supposedly, because I was born after dungeons and society became intertwined, so I have no idea what life was like before.

Dungeons are filled with resources essential for human survival. Whether it's rare metals or exotic foods no one's ever tasted, dungeons are a goldmine. But the main attraction is the magic stones you can get from defeating the monsters inside.

Yeah… Dungeons are full of monsters. These grotesque creatures that used to only exist in stories drop magic stones when you kill them—or sometimes they don't. Anyway, a few decades ago, some genius figured out how to use these stones for energy or something. I don't really get the technical stuff.

After that, countries around the world started pouring all their resources into conquering dungeons. At first, they couldn't handle monsters that bullets didn't even scratch, but eventually, kids started being born with something they called "magic power." Nobody knows why, but it turns out you can fight monsters if you have magic power. So naturally, governments started rounding up anyone who had it.

It's been decades since dungeons first appeared, but to be honest, the world's kind of stagnated. The reason is simple: dungeon conquests have pretty much stalled. They say there are about 500 dungeons worldwide, but less than 20 have been cleared all the way to the final floor. That's less than 4%.

The reason for the slow progress is that there are fewer people trying to conquer dungeons. And by that, I mean there are fewer people aiming for the final floor, not just those going in to make a quick buck. Nowadays, those who try are seen as thrill-seeking fools or reckless idiots.

I've rambled on, but the gist is that dungeons exist, and while there were some benefits to conquering them at first, now we don't need to reach the final floor to solve the energy crisis or keep the economy running. So, there's no demand for it anymore.

It's a tough world… We finally solved the energy crisis, but now there's no progress.

"...Sigh."

I let out a sigh as I look at the money in my bank account. It's not like I don't have enough. I've got assets worth tens of times what a regular salaryman makes in a lifetime. But I don't have anything to spend it on, and honestly, I'd trade it all for a more laid-back life.

I'm earning a lot, but I'm also spending it, trying to keep the economy moving. My place is pretty high-end, and I own multiple properties and land in Tokyo, Japan's capital. I even bought a top-of-the-line PC just for fun and dine at fancy restaurants once a week. But the thing is, Japan's economy is a joke. The more money you have, the more it just keeps piling up. Plus, since I regularly dive into dungeons, I make more than I spend. Even after taxes, I could easily live a life of luxury.

"It's not like having too much money is a problem, but this isn't exactly a typical high schooler's dilemma…"

Even though I make good money in dungeons, I've always thought that a higher education couldn't hurt, so I'm attending a private high school that's better than average. But between school and all the requests I get from the Dungeon Association, I'm barely scraping by on attendance. The season when everyone's talking about summer break is almost here, but I'm always working. If anything, I get more requests during the break.

My homeroom teacher, who knows my situation, says I should just become a full-time explorer after graduation instead of going to college. Despite being a high schooler, I was already a socially awkward loner, and thanks to all the work, I can't even make it to school half the time. I don't have any friends, and of course, no girlfriend or anyone I'm interested in. I hardly go to school, so I don't even know any girls my age.

I've got money, but does that make me a winner or a loser in life? I can't really tell.

I don't have any parents or a proper guardian, so I guess I could live however I want… But I don't even have the energy for that anymore. I'm starting to sound like a burned-out office worker, but I really miss the days when I could just explore dungeons without a care in the world.

If only I'd made more of an effort to make friends or find a party when I first became an explorer… Would I be living a more fun life now? Nah, no way… A socially awkward loner like me couldn't pull that off.

Thinking about impossible things is stressing me out… Maybe I'll blow off some steam in a dungeon.

The dungeon I chose to blow off steam in is the "Shibuya Dungeon," the closest one to both my house and school. Actually, I mostly operate around this dungeon.

The Shibuya Dungeon is located in Tokyo, Japan's capital. It's a famous dungeon, both for its difficulty and for its convenient location, attracting a lot of challengers. Even with all those people diving in, though, it still hasn't been fully cleared.

The dungeon is an underground labyrinth right beneath Shibuya Station. People often wonder why it had to appear in a place that's already a maze to navigate. The dungeon entrance and the Dungeon Association's branch office are located at the deepest part of Shibuya Station… Seriously, who thought it was a good idea to build a dungeon under a dungeon? Not that anyone knows who or why these dungeons were created anyway. It's an eternal mystery.

"Today, I'm challenging the lower floors of the Shibuya Dungeon for the first time!"

As I delve into the dungeon to blow off steam, I hear a loud voice echoing from a distance. Lately, I've been seeing people like this talking to themselves in dungeons… What the heck are they doing? Talking to yourself in a dungeon just attracts monsters. It's not like anything good comes from it.

"They say the lower floors are uncharted territory, but I'll be fine! There aren't many people streaming from the lower floors of Shibuya Dungeon, so I know you're all curious!"

I catch the words about challenging the lower floors. Dungeons are categorized by their floors, and the areas explorers can access are determined by their "Explorer Rank."

The terminology varies by dungeon and country, but in Japan's Shibuya Dungeon, the floors are divided as follows: Floors 1-10 are the Top Floors, 11-20 are the Upper Floors, 21-40 are the Mid Floors, 41-60 are the Lower Floors, and anything beyond Floor 61 is the Deep Floors. So right now, I'm standing at the boundary between the Mid Floors and the Lower Floors, which is Floor 40.

"Alright, let's go! You're all witnesses to history in the making—just kidding!"

While I'm thinking random thoughts, at my feet is a beast that looks like a wolf, yawning lazily with its yellow fur swaying. Just like its master, this creature seems pretty relaxed here at the bottom of the Mid Floors. It's probably because we can easily handle the monsters in this area.

Seriously, this wolf looks even more bored than I am. It was just fighting monsters a minute ago, and now it's acting like it's got nothing to do.

"Ready to head back?"

In response to my question, the wolf purrs and closes its eyes, but then it suddenly perks up, sensing something, and dashes straight towards the stairs leading to the Lower Floors. Honestly, I don't think it's cool for a shikigami to just run off without its master, but I've known this one the longest out of all my shikigami, so I guess it's fine… At this point, it's basically like having a pet dog.

"Guess I've got no choice…"

Even so, I can't just leave my shikigami unattended, so I start following it at a leisurely pace. It's the middle of a weekday, so this is probably the time when there are the fewest people in the dungeon. Even if a yellow wolf is running around, it probably won't draw much attention. I mean, there are way more monstrous-looking creatures in this dungeon, and beyond the Lower Floors, it's basically a den of horrors. If someone catches a glimpse of my shikigami, no big deal. We'll manage somehow.

Little did I know that this laid-back attitude would lead to all sorts of trouble later on. But at that moment, as I yawned and walked, I had no way of predicting any of it.