The Day I Was Betrayed

Just one minute after leaving the boss room.

An unexpected sight appeared before us.

Alto-san, who was leading the way, frowned suspiciously.

“What? The exit is blocked…?”

Beyond the short passage leading out of the boss room lay a vast hall.

Although it appeared to be a safe area, the entrance we had passed through on our way here was now inexplicably sealed by a sturdy door.

“What on earth is going on?”

After walking to the far end of the hall, Alto-san tilted his head in confusion and touched the door.

It happened immediately afterward.

Something appeared before us.

“GRRRRRAAAAAAAAAAAAH!!!”

A roar.

A deafening cry so overwhelming that calling it a mere roar would have been an understatement suddenly echoed throughout the entire hall.

“W-We’re under attack!?”

“Kyaaah! What is that!?”

“—! Everyone, behind us!”

While Garen-san and Sierra-san were still confused, Cedric-san was the first to locate the source of the sound and shouted a warning.

Responding to his warning, we turned around—and were left speechless.

In the center of the hall.

A monster was sitting in the very spot where there had been nothing just moments earlier.

It must have stood approximately four meters tall.

Its entire body was enveloped in pitch-black mist. Although its silhouette was humanoid, the sinister mist surrounding it made it impossible to believe that it belonged to the same category of living creatures as humans.

Judging solely by the atmosphere it exuded, it seemed closer to an undead creature.

In its right hand, it held what appeared to be a dagger—no, its enormous size made it easy to mistake the weapon for something smaller, but by human standards, it was actually a greatsword.

That greatsword was also shrouded in black mist, and the destructive magical aura it emitted was beyond anything words could describe.

Steeling myself, I checked the monster’s status.

When I saw the number displayed in the level field, my eyes widened involuntarily.

“Level 1000…!?”

This creature was overwhelmingly stronger not only than me but also than Alto-san and the others, who were around level 300.

The monster before us—the extra boss known as Necro Demon—had reached a level that only a select few adventurers could ever attain.

The other four must have checked its status and seen the same result.

Everyone present broke into a cold sweat at the hopeless situation that had suddenly befallen us.

Garen-san, the warrior, was the first to raise his voice.

“Hey, what are we gonna do, Alto!? Even we weren’t expecting a level 1000 extra boss to show up!”

Even Garen-san, who normally protected the party from any powerful enemy with his exceptional defense and unwavering determination, was trembling with fear.

With everyone looking to him for a decision, Alto-san’s expression twisted dramatically.

“We’re adventurers. If possible, I’d like us to defeat any powerful enemy we encounter, no matter how strong they might be—but…”

At that moment, Necro Demon took a single step forward.

An ear-splitting boom rang out, and the entire hall shook violently.

At the same time, the pitch-black mist surrounding Necro Demon billowed outward, sending the aftershock all the way to where we stood.

“—!?”

That alone was enough to make my knees buckle, forcing me to kneel on the ground.

The concentration of magical energy was simply overwhelming. It was as though I was being forcibly reminded of the enormous difference between us as living beings.

Although the effect wasn’t quite as severe for the others, they seemed to have experienced the same phenomenon, and everyone’s faces had turned pale.

Amid all this, Alto-san let out a frustrated groan.

“Kh… There’s no way we can defeat it. The difference in our levels is simply too great. But even if we try to escape, the exit we need to retreat through has been sealed by a sturdy door that shows no sign of opening. This place was probably a trap room designed from the beginning to imprison and eliminate anyone who entered…”

After analyzing the situation, he closed his eyes as though hesitating over something—

“…Phew. I guess it can’t be helped.”

—For some reason, I thought I saw the corners of Alto-san’s mouth curl upward unnaturally.

(Huh? What was that just now…?)

Had I merely imagined it?

Before I could reach an answer, Alto-san turned toward me with a serious expression.

“Shin! Use the ‘Escape Teleportation Crystal’!”

“————!”

The first people to react to his command weren’t me, but Garen-san and the other two.

“Hey, Alto, if you’re gonna use that, does that mean…?”

“So that’s what we’re doing?”

“Well, I suppose it was about time…”

I had no idea what Garen-san and the others were talking about.

Nevertheless, I knew exactly what I needed to do.

“Understood! I’ll use the ‘Escape Teleportation Crystal’!”

After answering, I took a magical crystal out of my luggage bag.

The magic item known as the ‘Escape Teleportation Crystal.’

As its name suggested, it was an item used to escape from a dungeon and return to the surface.

Alto-san had instructed me beforehand to activate this item if an emergency arose.

Following his instructions, I began pouring magical energy into the teleportation crystal.

“Alto-san! It’ll take about a minute to activate!”

When I shouted that warning, Alto-san nodded slightly.

“Got it! We can somehow hold it off for that long! Let’s do this, everyone!”

“Yeah!” “Of course.” “Understood.”

—For the next minute, a fierce battle unfolded before my eyes.

“GRRROOOOOAAAAAAHHH!!!”

With a roar so thunderous it threatened to rupture our eardrums, Necro Demon swung its greatsword with tremendous force.

Against this overwhelming opponent, Alto-san and the others spared neither their skills nor their magical energy, managing to maintain something resembling a stalemate, however briefly.

Watching the four of them fight with their lives on the line filled my heart with excitement.

(Everyone really is amazing…!)

They fought without flinching against an enemy vastly more powerful than themselves.

It was such an inspiring sight that I found myself wishing even more strongly to become like them someday.

And then, one minute later.

The moment the crystal was ready to activate, I shouted.

“It’s ready! Everyone, come over here!”

“Got it! Everyone, fall back together on my signal—”

A dazzling light gathered around Alto-san’s longsword.

Then, with a powerful downward swing, he unleashed the accumulated light.

“—Sacred Sword!”

“GRRRAAAAAAAAH!”

Necro Demon’s enormous body staggered backward slightly after taking Alto-san’s ultimate technique head-on.

Although the attack didn’t seem to have inflicted much damage, it was enough to buy us a little more time.

“Now!”

After confirming that, the four of them quickly rushed toward me.

Then Alto-san, who arrived last, held out his hand toward me and spoke.

“Shin, hand over the luggage!”

“Huh? O-Okay!”

Although I wondered why he was asking for it at a time like this, I handed Alto-san the luggage bag containing everyone’s items.

In any case, everything should have been ready now.

“Shin, we’re counting on you!”

“Yes! Teleportation Crystal—activate!”

The instant I poured the last of my magical energy into the crystal to ensure its activation, it emitted a dazzling radiance.

A massive magic circle appeared, and a transparent barrier expanded from it, enveloping those who would be teleported.

—Everyone except me.

“………………Huh?”

Unable to comprehend what had happened, my mind instantly went blank.

What had just happened?

I had activated the teleportation crystal exactly as Alto-san had instructed.

The magic circle had appeared, and the barrier had successfully formed.

Everything had gone according to plan up to that point.

The problem was that I was still standing outside the barrier.

At this rate, I would be the only one unable to teleport out of the dungeon.

I had no idea what had caused it.

All I knew was that things would end terribly for me if this continued.

“Everyone, there’s a problem! I’m the only one left outside the barrier—”

Just as I was about to explain the situation to Alto-san and the others and ask them what I should do…

An unbelievable sight appeared before my eyes.

“Heh, hehehe…”

For some reason, Alto-san was covering his mouth with his hand as though struggling to suppress his laughter.

No, that wasn’t right.

I finally realized it.

Alto-san wasn’t the only one laughing.

Quite the opposite, in fact—

“Ahahahahahahahaha!!!”

—All four of them were laughing uproariously as they watched me standing alone outside the barrier.