"Huh...? Cliffmatsu... what are you doing here...?"
"Iruma-san, you need to get to the library right now."
"No thanks... I'm extremely busy building a machine that'll let me die in maximum comfort..."
"We caught the Mastermind."
"Y-you serious!?"
Iruma, who'd been slumped in the dining hall listlessly tinkering away at something, heard me and immediately bolted for the library. Watching her go made a smile rise to my face all on its own.
'K... your plan really worked...'
If it hadn't been for his plan, we could've ended up in a catastrophic mess. Me included.
If he hadn't come to my room that day... the others, already teetering on the edge of panic, probably would've caused some irreversible disaster by now.
'Well then... guess I should go find the rest of them...'
With my heart feeling lighter than it had in ages, I stepped out of the dining hall to gather the others, and my thoughts drifted back to the operation to catch the Mastermind—the one that had begun the moment he came to find me.
.
.
.
.
.
"I-I'm so, so sorry...!"
"U-um... K-kun? What's going on...?"
"I've committed a crime worthy of death...!!"
"...."
When I opened the door, there he was. The instant he saw my face, he panicked—then dropped flat to the floor in a full dogeza.
The sight was so wildly out of sync with everything he'd shown me until now that I instinctively grew wary.
"W-why are you doing this?"
"Uh... well... I came to apologize for everything I've done up until now..."
".....?"
As he said that, he showed me the E-Handbook he was carrying.
"Th-this is..."
"It's the message I got on my first day here..."
On his E-Handbook, beneath the words [Survivor Privilege], was a message claiming that I was the Mastermind behind this killing game.
"Huh? But there's another memo here..."
"Ah! That's a personal memo! You don't need to look at that!"
The moment I tried to open the next memo, K cried out in alarm. I figured I should respect his privacy, so I gave up on pressing it and tapped the map displayed below instead.
"It's a map of the whole school...?"
"Yeah... for some reason, my handbook had something like that on it, so... I couldn't help suspecting Akamatsu-san... I'm really sorry..."
"K-kun, you don't have to be so formal with me."
"Huh? But..."
"It just feels awkward."
"Ah, then... yeah, okay."
Seeing him scratch his head with that blank, awkward expression, I suddenly started laughing.
"Pfft... puhaha..."
"U-um... why are you laughing?"
"No reason. It's just funny. The guy who was treating me like ice a second ago is now making that face and smashing his forehead into the floor... how could I not laugh?"
"Ah..."
"And... part of me is happy, too. Because you believed me."
"Y-you are...?"
"Yeah. Honestly, if I'd gotten a message like that, I probably would've reacted the same way. But in the end, you chose to trust me over that message, didn't you?"
"....."
"You came to apologize to me now, and that makes me happy enough to forgive you. So... you can get up now."
Once I finished speaking, K slowly, hesitantly rose to his feet. I watched him for a moment, then started asking the questions that had suddenly piled up in my head.
"But... what even is that message? What's [Survivor Privilege]? And what made you suddenly change your mind...?"
"It's dangerous to explain everything right now. If we keep talking here, the Mastermind might overhear us."
"Ah..."
"So I'll just say this. I have a plan to catch the real Mastermind. And for that plan... I need your help."
"My help...?"
"Yeah. The truth is... you're one of the only two people I can trust right now... and I absolutely need your help for the trick."
"....."
"Please. If we're going to end this killing game, then we have to—"
"Okay. I'll help."
When I answered firmly, he looked startled for a moment, then lowered his head and said,
"...Thank you."
"Y-you don't need to bow over something so obvious..."
"A-and... can I ask one more favor?"
"Hm? A favor?"
"From now on, I'm planning to keep acting cold so we can deceive the Mastermind... will you play along?"
"Yeah. If it's to end this killing game."
And just like that, our alliance was born.
"Y-you... you bastard...! What did you say to Akamatsu!?"
"...What?"
"N-no... Momota-kun! You've got it all wrong!"
"Wrong, my ass!! Her eyes are all puffy!!"
And so, the first mission of our new alliance was talking Momota-kun down after he completely misunderstood what he'd seen when K and I came out of my room.
.
.
.
.
.
"Y-you're..."
"Why are you here...?"
"Ah, well, y'see... so, uh..."
After that, I met up with Saihara and was just about to tell him the truth when Amami-kun suddenly walked into the library, and I nearly jumped out of my skin.
"Uh... so... hi?"
Then K-kun appeared behind Amami-kun, and our confusion only deepened.
"Why are you guys here...?"
A moment later, Saihara-kun shot the two of them a suspicious look and asked the obvious question.
"Um... well... I had something to discuss with K-kun."
"I thought you two didn't get along... what exactly did you need to talk about...?"
I carefully approached the two of them, both wearing troubled expressions, and whispered,
"K-kun, don't tell me... the other one of the two people you said you could trust was Amami-kun?"
"Yeah... he's the victim, so there's no way he could be the Mastermind... ah, anyway, Amami-kun is trustworthy. So after I left you, I persuaded him and brought him here."
"The victim?"
"Ah, it's nothing! Forget I said that."
"But didn't you say the Mastermind might overhear us?"
"...You don't need to worry about that. Before coming here, I already confirmed where everyone was."
"Really?"
"Really. Aside from Iruma-san, Chabashira-san, and Shirogane-san in the dining hall, and Oma-kun and Shinguji-kun in the dorms, everyone else is outside searching for an exit right now. So we're the only ones here."
"...Including Saihara, of course."
At K's words, Amami turned and started eyeing Saihara suspiciously instead.
"U-um... Akamatsu-san? Guys?"
"K-kun, is Saihara-kun someone we can trust?"
"...Probably. It's not impossible, but if you ask me, Saihara can be trusted."
"There's no way Saihara-kun is the Mastermind! He just told me about the hidden door he found!"
"That's true...? If he were the Mastermind... he never would've done that."
"Then yeah... I think we can trust Saihara too. In that case..."
After that brief exchange, we all turned toward Saihara-kun, who was staring back at us in total bewilderment.
"...Looks like we've recruited a new ally."
And just like that, Amami-kun and Saihara-kun joined the anti-Mastermind alliance.
.
.
.
.
.
After that, everything moved at breakneck speed.
Once K gave Saihara a simple explanation of the situation and brought him into the anti-Mastermind alliance, he started laying out the plan to catch the Mastermind.
To be honest, when K asked for my opinion on "what kind of trick I'd use if I had to kill the Mastermind," then smacked his knee and declared we should recreate exactly that, I was more than a little dubious.
But I'd already decided to trust him, so I chose to trust him all the way.
Anyway, according to him, the instant the trick failed, the Mastermind would open the hidden door, come out, and try to attack. We decided to seize that moment.
The evidence would be preserved in photographs—Saihara-kun and I would get the cameras—and Amami-kun, the strongest fighter among us, would hide in the library and ambush the Mastermind.
After parting ways in the library, we began the plan in earnest the next morning in the dining hall.
First, to deceive the Mastermind, K began the performance he'd named his "vile acting," and just as we'd rehearsed, Amami-kun and Saihara-kun tore into him.
After that, K drove the misunderstanding deeper by asking about [Ultimate Hunt] in front of everyone, then left the dining hall and started monitoring what the others were doing so he could keep the Mastermind in check.
Meanwhile, once everyone scattered, Amami, Saihara, and I exchanged glances in the dining hall, then carefully made our way to the library.
.
.
.
Once we reached the library, we moved exactly as planned. Saihara-kun installed cameras in spots that could capture both entrances and the moving bookcase.
Of course, the camera aimed at the bookcase would flash because of my trick. K-kun would see it, pretend to get curious, and approach.
Meanwhile, I climbed the stepladder and started stacking books to create a path for the shot put ball to roll down from Classroom A on the first floor through the vent piping.
Even though it was my idea, the trick was honestly a little terrifying. If anything went wrong, it really could kill someone.
Well, Saihara-kun and Amami-kun had both advised me on the design, and we made absolutely sure it would miss K-kun no matter what, so that wouldn't happen.
"Let's trust ourselves. Right now, that's all we can do."
Come to think of it, after finishing the camera installation, Saihara turned around and said that.
"...Right?"
"Of course."
If some third party had seen that scene, they probably would've been utterly baffled. Amami-kun was hidden inside the pile of books Saihara-kun had stacked earlier.
.
.
.
.
.
"By the way, you hid everything properly, right, Saihara-kun?"
"Yeah, perfectly. Unless someone inspects things closely, they won't notice."
"I see... then that's a relief."
By the time we entered the classroom to wait for the plan to unfold, there wasn't much time left. I only managed to calm down after Saihara confirmed that he'd hidden the three cameras—and Amami-kun—properly.
After that... I was so happy to have a chance to talk honestly with Saihara-kun for a while, but then...
"".....!!!""
Out of nowhere, that murder-inciting video started blaring across the entire school, and when a huge number of the others—including K-kun—rushed underground, I was thrown into complete confusion.
I got so tense that I grabbed a broom nearby and started cleaning just to keep from falling apart.
Then Saihara-kun came in and told me everyone was in the arcade. Only then did I finally relax, set the broom down, and take out the shot put ball I'd already hidden in my bag.
"Akamatsu, throw that in and hurry up!!"
"O-okay!!"
When the alarm finally went off, I did exactly as Saihara said—I tossed the shot put ball into the piping, then stormed into the library together with everyone from the arcade.
And that was how we managed to catch Shirogane Tsumugi, the Mastermind behind this killing game.
So now... this killing game should be over.
And yet that obnoxious murder-inciting video was still blaring away, and for some reason, it gnawed at me.
.
.
.
.
"I see... so the four of you managed to catch the Mastermind..."
"Nishishi... so when I asked why you were putting on that fake act, K-kun, and you just clenched your teeth and ignored me, this is what you were up to! You should've let me in on it. Missing out on something this fun is a real tragedy, y'know?"
"S-so... I wore myself out fighting with you for no reason? Man... what a waste of effort..."
"Nyahaha~! Then it's okay if we use Shirogane-san as a human sacrifice, right?"
"Pyahaha! Or better yet, how about we toss her into my custom Heart-Pounding Pleasure Paradise Mark II?"
"Ngh... anyway, now that we've neutralized this creep, the killing game's over..."
Thanks to Akamatsu running all over the place to gather everyone, it didn't take long for the library to fill up with students.
"......"
"This girl looks completely out of it."
"You bastard...! Why the hell did you do this...?"
"......"
No matter how relentlessly everyone pressed her, Shirogane just stared blankly at K with a hollow, absent expression.
"Something's... wrong..."
"Hm? Akamatsu-san? What do you mean?"
In the middle of that suffocating scene, Akamatsu muttered in a trembling voice, and Saihara, standing beside her, asked the question.
"Why... why is that disgusting video still playing even though we caught the Mastermind? And... why haven't Monokuma and the Monokubs shown their faces at all...?"
"Yeah, something's off. At the very least, I thought Monokuma would show up and start threatening us."
While Akamatsu and Saihara exchanged uneasy words, the others began tightening the screws on Shirogane.
"Shirogane, you're finished. So before this gets ugly, stop this killing game and let us out."
"And if you're thinking of threatening us with Monokuma... you'd better prepare yourself."
"That's right~! Before we offer you up as a sacrifice, you'd better shut off that creepy video~!"
"........"
"This isn't getting us anywhere!! Just wait a second, I'll go get my custom Heart-Pounding Pleasure Paradise Mark II right now—"
"Upupupu!! What are you all doing gathered here?"
"...Gah, shit!! Wh-what the hell!?"
Iruma, who'd been heading toward her lab with a deeply suspicious grin, shrieked and collapsed to the floor the instant Monokuma appeared out of nowhere.
"Monokuma, you'd better drop the threats. We already caught the Mastermind."
"Yeah! You're finished now!"
"You'd better let us out quietly. Otherwise, Shirogane will—"
The others had the upper hand now that they'd captured Shirogane, the supposed Mastermind, and they tried to negotiate with Monokuma from a position of confidence, but...
"Okaaay then! One minute and thirty seconds remaining! Emergency! Emergency!!"
"...What?"
At Monokuma's next words, everyone froze solid.
.
.
.
.
.
"W-wait! What are you talking about!?"
"Y-you mean you don't care what happens to Shirogane!?"
"Upupupu? What are you talking about?"
"Because... Shirogane is... the Mastermind behind this killing game...!"
"Upupupupupupu!! What are you even saying!? Shirogane is the Mastermind!? She's not the Mastermind!"
".....What?"
As Monokuma burst into manic laughter, Shirogane—silent until now—went deathly pale and finally spoke.
"Wh-what are you talking about...?"
"More precisely, she isn't anymore!!"
"M-Monokuma...?"
"You're 'eliminated,' Shirogane! What a shame...!"
".....!!!"
"Now then, forty seconds remaining! Why don't you hurry up and commit a murder even now!?"
"N-no... th-that's impossible... I..."
"Thirty-nine, thirty-eight, thirty-seven..."
"I am...! Eno...!!"
Pajiiiiing!!
"Siiiii...."
Shirogane tried to scream something in desperation, but before she could finish, Monokuma whipped out a flash from somewhere and fired it. She collapsed on the spot.
"Upupupu... well, even someone else only figured out after a long, painful tumble that blindly worshipping game knowledge is a bad idea... so maybe this was just beyond you?"
"Wh-what is this..."
"Nishishi... I don't know what's going on, but this looks really bad!"
"Twenty seconds, nineteen, eighteen..."
"I-I don't want to die!!"
"B-but with Shirogane gone, there shouldn't be a huge swarm of Monokumas...! So let's fight!"
"Yeah!! Fine by me!! We'll smash them with our own hands!!"
"G-Gonta will do his best! Monokuma's no problem at all—"
"Hey! Did ya forget about us!?"
"Dad, all we gotta do is wipe these guys out, right!?"
"Exciting! Dynamic! I'll stomp every last one of them to death!"
"Tsk tsk... see? You should've committed a murder sooner..."
"......"
The moment the Exisals appeared behind Monokuma, Chabashira, Gonta, and Momota—who had been about to charge him—stopped dead in their tracks.
"Ten seconds, nine, eight..."
"Then someone kill me right now. If you do, maybe we can stop the massacre—"
"...Everyone, run. I'll handle things here somehow."
"B-before I die... c-could you at least let me test my Pleasure Paradise Mark II once... p-please...?"
"Y-Yumeno-san! Let's get out of here with teleportation magic!!"
"I-I'm out of mana right now!!"
"Damn it!! I can't die here before I even make it to space!!"
"Seven seconds, six, five..."
"Th-the library doors are locked!!"
"I-it's over... we're all gonna die hereee..."
"Nyahaha~! Everyone, stop panicking and pray to God with me~!"
"Nishishi... well, if it's come to this, we've got no choice... Kiibo! Self-destruct!!"
"I-I underst— no, I mean, there's no way I have a function like that!!"
"Four seconds, three, two..."
"...Am I finally going to be with my sister?"
"To fail everyone's requests like this..."
"If I was just going to die like this... then why did I live so fiercely...?"
"A-Akamatsu-san! Get behind me!!"
"Saihara-kun!!"
"Damn it... Kirigiri... I don't know who you are, but... I'm sorry..."
"One second!!!!!!!!"
Just before the countdown reached zero, every gun barrel mounted on the Exisals swung toward the students in unison.
Everyone felt death bearing down on them and plunged into full-blown panic, but then—
"I was juuust about to go ding... but good news for you! Negotiations have just concluded!"
Monokuma's oily, absurdly casual announcement made everyone stop panicking and stare at him in bafflement.
"Honestly... to think I only accepted the proposal after hearing his desperate plea with just one second left before the negotiation deadline... those two really do have a great relationship..."
"W-what are you talking about...? Negotiation...?"
"Upupupu... actually, this countdown was for negotiations... ah, but you don't need to know that, do you?"
"I-I don't know what you're talking about... but are you saying you're letting us live...?"
"Of course! I can't tell you the details, but... things worked out nicely!"
At that, the students' expressions brightened—just a little.
"And now... for a shocking announcement!!"
But the moment Monokuma said that, their faces curdled all over again.
"I'm so done... I just want to rest already..."
"How long are you planning to toy with us...?"
"Whatever, at this point, nothing can really surprise me anym—"
"Allow me to introduce a new transfer student!!"
"...Whaaat!?"
Momota, who'd been muttering in exhausted resignation, shouted in disbelief, and Monokuma grinned as he pointed toward the library doors.
"Now then... please come in!!"
A moment later, the tightly sealed library doors opened, and someone began walking in.
"Upupupu... I wanted to just kill her, but... can't be helped. A deal's a deal... and besides, this might make things even more fun!! Upupupupu....!!"
"....K, long time no see."
The new transfer student walked up to the group, stopped in front of K, and asked with an awkward smile.
"Uh... um..."
K stared at her, trailing off for a moment before finally asking,
"...Are you Kirigiri, by any chance?"
"..........."
Her face twisted instantly at those words, but after thinking something over for a few seconds, she flushed red and opened her mouth.
"...H-how did you know?"
And so, Mukuro Ikusaba joined the killing game as Saishu Academy's eighteenth Ultimate.