"Were you and your fallen companion both fourth-tier?"
Dekan brought the challenger to the infirmary and helped patch up his wounds a little before asking.
"Yes."
After answering, the challenger glanced nervously at Dekan and Cornelia. "Are you two fourth-tier... or fifth-tier?"
"Fourth-tier. We're all fourth-tier."
Dekan waved a hand and replied casually.
"..."
The challenger had plenty of doubts, but he didn't dare voice them.
He strongly suspected that at least one of Dekan and Cornelia was fifth-tier.
Even if neither was fifth-tier, they were the sort of geniuses who could fight at a fifth-tier level despite being only fourth-tier.
The state of the wrecked infirmary probably had something to do with those two.
Without terrifying combat power, they couldn't possibly have trashed the infirmary like this—or made the school doctor vanish into thin air.
Most baffling of all, neither of them had a scratch on them.
Dekan asked again, "By the way, was the classroom where you failed difficult?"
Challenger: "...At first, we didn't think it was particularly hard. But once we figured out its mechanics, it was genuinely awful."
"Oh? Tell me how it works. Maybe I'll go clear it."
Dekan seemed even more interested now, his eyes practically glowing.
It was likely an elite room.
Since the difficulty was high, its exploration rating would be higher too. They might even find information about the boss room.
"Let's just avoid that classroom. I really don't see any hope of clearing it... I can't risk getting you hurt..."
"Tell me how it works first. I'll judge the difficulty myself."
Dekan remained supremely confident, giving off the air of an absolute superior.
Beside him, Cornelia was just as unruffled. Her expression was cold, and she remained silent, as though no powerful enemy could ever make her so much as twitch.
The challenger carefully observed the two of them. He was momentarily stunned, and his heart began to race despite himself.
For an instant, he had the strange feeling that these two were the true rulers of this Demon School.
This was the aura of absolute power!
Maybe... they really could help him and his companions avenge themselves!
The challenger took a deep breath and lightly rubbed his chest. With a grave expression, he looked at Dekan and Cornelia and said, "It's a Music Classroom. Its mechanic is called the Demon Choir."
"The Music Teacher plays an instrument, and the students have to join the Demon Choir and sing."
"When you first enter the classroom, you can listen to the choir perform up to three times. You also get fifteen minutes of free time to practice."
"After that, you have to join in. If you sing three notes wrong, the teacher's kill mechanic activates."
"If you attack another student, the Demon Teacher will kill you too."
Dekan's brow furrowed slightly.
He didn't think the mechanic was all that twisted. In fact, it seemed pretty ordinary.
It shouldn't have been enough to trip up fourth-tier challengers.
Unless the two of them were tone-deaf.
"Are there other traps in the game besides the obvious rules?"
Dekan asked.
"...Yes! Actually, the Demon Teacher isn't particularly nasty, but those damned demon students in the choir ostracize anyone new. They seem to have a secret signal. If a new student joins the choir, they deliberately change how certain parts are sung as a group."
The challenger answered through gritted teeth.
"And then the teacher rules that you sang it wrong?"
"Yes. 'Right and wrong are relative, not absolute.' We only discovered that trap in the rules after we'd been screwed over. Even after using up all three chances, we still couldn't figure out the students' secret signal for changing the tune..."
The challenger's face was full of pain and regret, and his eyes had turned red.
Dekan rubbed his chin, thinking.
If that was how it worked, then he agreed that the classroom was a little twisted.
The previous rooms had all been about outsmarting the teachers. Now the Music Classroom was letting the students cause trouble too?
He'd thought all those demon students were perfectly well-behaved.
Who knew some of them could be so ill-mannered!
Our school absolutely does not tolerate students bullying one another!
Dekan was going to put a stop to this.
"Cornelia, let's go!"
"Okay."
"Wait, don't you want to hear what we've learned so far?"
The challenger watched the two of them prepare to leave the infirmary without hesitation and asked anxiously.
"No need. The viewers watching the stream outside don't want to hear a complicated analysis of the mechanics. They just want to see me whip the Demon Choir into shape."
"...You brought an Observation Program?"
"New streamer."
Leaving him with those words, Dekan and Cornelia strode out of the infirmary, leaving the challenger staring after them in utter confusion...
"I haven't even told them where the Music Classroom is..."
"Do they even have a map of the school?!"
"How have I never heard of people this amazing..."
The challenger sat in the infirmary, muttering to himself in a daze.
Dekan and Cornelia headed toward the Music Classroom.
By now, the corridors of the Demon Academy had practically become Dekan and Cornelia's backyard.
What annoyed them was the bunch of idle demon students wandering around. The school had gone back to holding classes again.
In any case, they'd have to switch the school back to class mode before challenging the Music Classroom.
"Cornelia, this classroom's better suited to a solo challenge. Wait for me outside."
"Okay."
When they were nearly at the Music Classroom, Dekan took a Demon Pass out of his pocket and handed it to Cornelia.
They'd looted it earlier from the corpse of a Demon Teacher in a classroom Batchel had swept through.
There hadn't been any Demon Passes in the broadcasting room or the infirmary, but the teachers in the other two classrooms had them.
At first, they'd each taken one.
Now Cornelia had both of them. Each pass could keep her safe for at least half an hour.
A music class lasted only an hour. Even if The Dean stood right beside Cornelia, she'd be safe while waiting outside.
"Cornelia, I'm going in."
"Mm. Be careful."
Then Dekan pushed open the Music Classroom's door and went in alone.
Light flooded his vision at once.
The Music Classroom looked like a classical concert hall.
Unlike the dim corridor, it was bright inside. The stone columns were carved with all kinds of lifelike images, and the walls seemed to be made of flawless white jade.
At the very front of the hall was a circular stage, its surface covered with thick, soft carpeting. Various instruments stood on either side, while two rows of steps rose through the center. Twenty demon students stood on them.
That must be the Demon Choir.
The most eye-catching figure in the room was the male demon standing in front of the choir. He wore a black suit and gold-rimmed glasses, and looked refined, though a little stern.
"Welcome to the Music Classroom."
Noticing Dekan's arrival, the Music Teacher turned around and greeted him with a composed smile.
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