What Is Mystery?

Three of them.

What should he ask?

Anything he could see and touch, he could simply look up in the Backrooms Chronicle. So the best use of his questions was to probe for concepts the Chronicle would never give him—things he absolutely had to understand before moving on.

"What is Mystery?"

Before the question had even finished leaving his mouth, Balan's smile vanished. His eyes narrowed to a cold, piercing slit, and he looked at Minel as if he meant to see straight through him.

A brief silence.

Then Balan smiled again—this time far more knowing than before.

"How does a guy from the 1st Floor know about that? That's not a concept you can learn down here."

"You mentioned it earlier."

"I did?"

"Yes."

Balan regarded Minel with a flicker of suspicion, then seemed to remember and nodded.

"Ahh. Right. I told you to experience a lot of mysterious things. But that alone wouldn't be enough to realize that 'Mystery' exists as a separate concept."

The Backrooms Chronicle. It was the kind of treasure even veterans couldn't easily get their hands on—so he couldn't mention it.

"A concept?"

When Minel asked again, Balan looked him over once and answered flatly.

"Mystery is exactly what it sounds like. It builds up every time you see something mysterious. Once it settles into your mind, it almost never goes away."

"Builds up…"

"After you've seen something strange, you need something even stranger to be surprised, right? It's like that—how used you are to the bizarre. If that still doesn't click, just think of it as a kind of level. The Backrooms loves turning everything into numbers."

Seeing mysterious things?

Something flashed through Minel's mind.

"That burning pain in the eyes…"

Balan nodded again.

"Sharp as ever. That's right. That's Mystery Pain—what you feel when Mystery is accumulating. Be careful with it. See something too mysterious all at once, and you'll go mad on the spot."

"…"

"You have to build Mystery slowly. Get used to it bit by bit. That's the only safe way to climb. If your eyes hurt so badly you think you're dying, it means your mind can't handle it yet—so don't go digging for more."

Minel thought he understood the feeling well enough.

"It's similar to Wildness, then?"

Balan was smiling openly now.

"Aside from Wildness settling in the body and Mystery in the mind, yeah—pretty similar. Honestly, Mystery is something you only start hearing about on the double-digit floors. Most people on the 1st Floor don't even know what Wildness is, and here you are getting a proper early education, huh?"

The double-digit floors. In other words, the 10th through the 99th.

The way Balan said it meant he had come down from at least that high—perhaps from far higher than Minel had imagined.

So how many floors were there above the 100th?

Minel changed the question.

"Second question. How far up do I have to go to escape this place?"

Balan looked at him for a moment, then gave a slight nod.

"Escape-related items are hidden all over the Backrooms, so I can't pin it down to a specific floor. They spawn completely at random."

"Is it hard even for you, Balan?"

If it was difficult for him, that would mean climbing past the 100th Floor. Fortunately, he shook his head.

"No. I've had quite a few chances to leave myself. You run into them now and then as you climb the upper floors. I actually got out three times."

He had left the Backrooms three times?

Then had he come back each time?

"Why did you come back…"

Balan cut him off.

"Why come back? Heh heh heh. Well, when I first arrived on the 1st Floor, I wanted out more than anyone. So of course you wouldn't understand."

"…"

"But once you adapt to the Backrooms, something in you shifts. You'll see it yourself as you climb, Minel. This hell has a very peculiar flavor to it. Once you've set foot in it, no one ever truly gets free."

"…"

"You've got one question left."

Minel couldn't understand it at all. To leave three times and still return to a place where you couldn't even guarantee you'd live through the day—every time he stared up at that oppressive ceiling, the blue sky he pictured in his head felt as distant as a dream. He didn't need fine food. Just one breath of clean air in an open park would have been enough to keep him going.

And yet Balan had left and come back. Back to this dark, damp, dangerous, uncanny Backrooms. Not once or twice, but three times.

It was impossible to accept. There had to be some reason he had no choice but to return.

But Balan's face had settled into a quiet blankness that said there would be no further explanation. Personal questions, it seemed, were not allowed.

Minel turned the final question over carefully and chose with absolute caution.

"How do I climb to the 2nd Floor safely?"

"Once enough Mystery has built up in your mind, the truth of the Backrooms starts to show itself. If that staircase looks ordinary to you, then it isn't."

"…"

"That advice will stay useful for a long time. Make sure you remember it."

In other words, the emergency stairs were safest precisely when they looked anything but ordinary. In the end, he would have to go and see for himself.

"Thank you."

At Minel's thanks, Balan shrugged.

"Somehow I get ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠the feeling you'll climb all the way up to where I am. See you on the upper floors someday."

As if he had nothing more to say, Balan pulled out his phone again and started walking slowly toward the emergency stairs. He jabbed at the screen, trying to place a call, but the connection kept failing, and irritation crept across his face.

If Balan had handed him something, Minel might have grown more wary. But the way the man simply gave the necessary information and turned away only made him more trustworthy.

Minel quietly opened his inventory.

At the clear chime, Balan glanced back. Minel drew out a broken phone and held it out to him.

"Mine's broken too, but I thought this ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠one might still work for you."

Balan narrowed his eyes, looking from Minel to the phone and back, then stepped closer and carefully took it. After a brief inspection, a faint smile spread across his face.

"With this… it might just work."

He pulled out his own phone, turned it over in his hands, and began disassembling the parts. Then he took apart the broken one Minel had given him as well and started selecting components from both devices, fitting them together. Unnecessary pieces clattered aside as he calmly assembled the whole. Before long, a soft light bloomed across the screen.

"Done."

Smiling, Balan set to work at once. Each time he pressed a number, a bright little click rang through the room. But his fingers never stopped.

"How long is it?"

"Hm? Oh—about forty digits."

"…"

"Memorizing it is half the work."

After a long stretch of tapping, he finally hit the call button. The ring tone connected, and Balan lifted the phone to his ear. As he waited in silence, a growing brightness spread across his face—like a man reconnecting with someone he had long forgotten.

"Can you hear me?"

He spoke lightly, and a woman's voice answered from the other end. But it was too soft for Minel to make out. All he could catch was Balan's half of the conversation.

"It broke. Yeah. For real. I told you ages ago I needed another spare. Hm? I got one. Yeah, on the 1st Floor. A newbie junior gave it to me. Name's Minel—seems like a decent kid. I didn't take it from him. Didn't kill him either. He just handed it over because he was grateful I took him on as a junior. Who knows about that. Yeah. I think he might climb all the way up to where we are. I can see the potential."

Balan looked at Minel and grinned. Minel could only stare back, unable to read the meaning in that smile.

"The Smiler I found by chance. I tore through the entire lower floors, and it turned out to be on the 1st. I figured I'd take one last look around before heading back, and the second I stepped out of the stairs I ran into it. Yeah. Insane luck. The item even dropped on the first try. And I took it down on the 1st Floor, no less. Yeah. White smile, just like always. Damage rate? What do you take me for, asking that. What's so hard about taking down a Smiler? A newbie? Ah, yeah. Put him in the guild? Really? You're serious? Never thought I'd hear that from you."

Balan glanced sidelong at Minel, then continued.

"Not yet. I'll make the offer the third time we meet. Come on—you need at least that much of a connection before you're fit for our guild, honestly. Even if he is a guy who came up from my 1st Floor, that's a little too much favoritism. Yeah. Let's keep an eye on him. At the very least he should break through the 10th Floor on his own. Yeah. Alright. See you later."

Balan hung up, stowed the phone in his inventory, and turned to Minel.

"I'd rather give the phone back if I could, but I've already rebuilt it, so that's not easy. A senior can't go into debt with his junior, so take this instead."

He pulled an item from his inventory and tossed it lightly toward Minel. Minel caught it on reflex. The texture under his fingers was thick and soft. Looking closer, he saw a leather jacket stained with pale blood that repeated washings had never quite erased. The crimson had soaked in like an old memory, and though the fabric was worn, it was still solid—used, but sturdy and practical.

"It's the armor I used when I was climbing. You've got weapons, but I didn't see any armor on you. Armor matters, though. In the end, it's what your life is worth."

"…"

"I'm giving it to you for the phone, so make good use of it. It'll serve you a long time on the single-digit floors."

Balan turned without hesitation, putting his full back to Minel as if he had no further business with him. If the man had been harboring some scheme, he would have shown his true colors by now. But there was no falsehood in that bearing. Watching that unburdened retreat, Minel was certain: Balan truly meant him no harm.

Perhaps that was why a question he would normally have swallowed rose to his lips before he could stop it.

"Do you happen to have one more?"

"…"

"Something for a woman."

If a veteran like Balan ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠was handing over defensive gear, its performance wouldn't be ordinary. Minel was sure it would be a great help for Hina's survival as well.

Balan looked at him in silence. Something like understanding flickered in his eyes, followed by a stretch of quiet. Asking for more might have been too much after all.

Then Balan's mouth curved, and he grinned.

"You've got a woman with you in the middle of all this? Impressive."

"…"

"Well. I can spare one more."

He opened his inventory, quietly drew something out, and tossed it to Minel. What landed in his hands was a soft, light women's cardigan—perfect for Hina to wear.

"Thank you."

Minel nodded, but Balan kept staring at the cardigan. He watched it with a strange look, then blinked.

"The leather jacket is yours, but that cardigan is only on loan. Give it back later."

"Ah… yes."

"Don't tense up. It just means we'll meet again. Take good care of your girl."

Balan laughed lightly, turned his back, and walked away at an easy pace. The way he disappeared toward the emergency stairs without a shred of wariness felt oddly human. When Minel had first seen him, he had seemed less like a person and more like some finely trained machine.

Then, suddenly, Balan stuck his head back through the doorway.

"Ah. One more piece of advice."

"Yes."

"When you can climb a floor, climb as fast as you can. Don't dawdle and hang around on the lower floors too long."

"…"

"If you get too used to the comfort of the lower levels, you stop wanting to go any higher. That's how people end up as quitters."

"…"

"I won't stand for a junior of mine turning into a quitter. If I hear a rumor like that, I'll come down myself and kill you out of pure embarrassment."

"…"

"If you get too worn out along the way, hang on with good food, fine sights, and fun diversions. But never settle."

"…"

"See you up above, Minel."

With a smile, he vanished toward the stairs once more.

Minel thought back to the impression Balan had left when they first met in the elevator. Back then, he had felt less like a person and more like a well-trained machine. Now he was simply a very kind veteran—one who wanted to explain everything, one piece at a time, to a newbie.

Alone again, Minel began gathering the Blood Crystals scattered across the floor one by one. To Balan they would have been meaningless scraps; to Minel they were the foundation of survival. As he worked, he turned Balan's words over in his mind.

Mystery and Wildness…

Minel quietly steadied his breath, drew out the Backrooms Chronicle from his inventory, and began checking the items Balan had given him one by one.

Minel's eyes went wide.

+9. That had to imply an enhancement system.

Silence and Noise automatically adjusted their levels according to the highest floor their special effects had reached. Taking that into account, it was highly likely that items obtained on each floor had their performance scaled to that floor's standard as well.

Which meant… these pieces of armor Balan had given him would still be effective by 10th Floor standards at minimum. In other words, for Minel and Hina on the 1st Floor, they were absurdly high-performance gear.

Minel hesitated for a moment. Theory was only theory—without a direct test, he couldn't be certain. He found a sturdy-looking chair nearby, carefully spread the leather jacket over it, adjusted the distance and angle, and quietly squeezed Noise's trigger.

Bang—!

A clear crack split the air as an energy round fired. The bullet streaked straight toward the jacket.

The instant Noise's shot touched the leather, every trace of impact vanished as if sucked into a vacuum. No sound. No mark left behind.

Considering the power Noise had shown until now, this was simply absurd defense.

There was no reason to hesitate. He picked up the jacket at once and put it on. It fit his body perfectly—soft, yet firm to the touch.

On his way toward the storage room where Hina was waiting, another item suddenly came to mind. The femur he had set aside when he first crossed paths with Balan. At the time he hadn't known how to use the Backrooms Chronicle, and so much had happened afterward that he had forgotten about it. Meeting Balan again had brought it back.

He pulled out one of the femurs and read the first page of the Backrooms Chronicle.

Minel stopped walking.

His pupils went unfocused, and he stood rooted to the spot.

It wasn't the threatening word Transcender. It wasn't even the rarity of the Unique grade.

What froze him solid was a single phrase: ten thousand floors.

"T-ten thousand floors?"

His lips trembled. Even as he said it, he couldn't be sure the words made sense.

Minel was not a man who startled easily. But now his whole body seemed to be shaking.

Up through the 99th Floor, he could still understand. Hellish as it might be, it still fell within the limits of perception. But ten thousand floors…

That number felt like a bottomless abyss, scraping away even the last shred of reason he had been clinging to.

In that instant, a burning pain flared through both of his eyes—as if they were being seared from within.