A Mustard Seed Of Doubt

Sienna's POV

The campus had returned to its usual rhythm, the calm of vacation fading into the familiar chaos of schedules and expectations. Students moved with purpose, the air buzzing with conversations about upcoming exams and lingering holiday memories.

Just as I adjusted my bag strap, my phone vibrated. A notification? Not unusual—I did have a handful of people I spoke with. But a flood of messages? That was where I drew the line.

Unlocking the screen, I was met with something that made my steps falter.

"Sienna is indeed a genius. Finding out an exam is no small feat."

The words spread like wildfire across the student forum.

A praise? An acknowledgment? Or a well-placed trap?

It didn't matter. The illusion I had carefully woven—being an unremarkable student, neither weak nor exceptional—was at risk.

Who could have posted this?

Digging further, I found the source: an anonymous account. Newly created. The date of registration? Just minutes after I had posted a seemingly harmless comment about the structure of the last exam.

A coincidence? No.

Someone had been watching. Someone had taken what I said and twisted it into something undeniable.

I inhaled sharply. This was a deliberate move.

Still, it wasn't absolute proof. I could deny everything. I had to.

As I stepped into the classroom, the air shifted. Conversations quieted, eyes flickered toward me. Some curious, others unreadable. But the one that held my attention was Katsuragi Kouhei. His fingers tapped lightly against his temple, his gaze locked onto me in thought.

Ai Morishita was the only one unfazed, scrolling through her phone. Masumi Kamuro observed me closely as I made my way to my seat.

Then, a voice sliced through the silence.

"My, my, my. It seems we have quite the capable individual among us. Surely, their talents could help maintain our standing as Class A?"

The words dripped with mockery, laced with a probing intent.

Kosei Sanada.

I didn't react. Responding would solidify the suspicion. A false step here wouldn't change the fact that I had been found out, but it would dictate how they intended to treat me—an asset to exploit or an enemy to isolate.

Ai shifted slightly at Kosei's words, though she said nothing. He adjusted his glasses, leaning back into his chair.

"Deducing an exam with little to no information... quite the feat, really. I assume whoever accomplished this wishes to keep their abilities hidden."

"Fufufu," a soft chuckle followed. "You're as perceptive as ever, Kosei. But, they still haven't said a word."

Sakayanagi Arisu.

The moment her voice reached my ears, something clicked.

The timing. The anonymity. The deliberate wording of the post.

It was her.

She had created that account. She had spread the rumor.

But instead of confirming her involvement, she dangled it just beyond reach, waiting for me to react.

I kept my expression steady.

"Wait, are you saying someone from another class solved this exam too?"

My tone was carefully measured—just enough curiosity to shift the conversation.

I wasn't playing dumb. I was reframing the narrative.

The post had gone up after I had gone to bed. That was my alibi.

Hashimoto leaned forward slightly, gauging my reaction. "You mean you don't know?"

I tilted my head. "Something happened on the forum?"

"Yeah," Hashimoto confirmed, his expression unreadable. "Someone posted a highly accurate guess about the next exam. The reasoning was airtight, not a stretch at all."

"That's impressive," I mused, my voice light. Then, with a casual glance at Ai, I added, "But Ai Morishita did the same thing, didn't she?"

His brows furrowed slightly, caught in thought.

Perfect.

By redirecting the conversation toward Ai, I split the suspicion. Now they had to reconsider whether I was the mastermind or just another observer.

Ai sighed as the attention shifted to her. "Ahhh, it's true. Sienna pointed out an inconsistency, and I pieced things together."

Kosei frowned, his eyes flickering briefly toward Sakayanagi before returning to me.

"So you're saying you're not the one who made the full analysis?"

A test. He wanted to see how I would react.

I smiled. "Of course not. I think I'm smart, but Ai's the real detective here."

By acknowledging my intelligence yet reinforcing Ai's superiority, I built a perfect defense—competent but not exceptional.

Sakayanagi's voice cut through the moment.

"Fufufu. So you're saying you were falsely accused? Hard to believe it was without reason, isn't it, Sienna?"

She was pressing me again, this time with a sharper edge.

I let my fingers hover over my phone before 'noticing' the post.

"Huh? This is crazy. Who'd do something like this? People will say anything for attention."

Sakayanagi held her smug expression, but she didn't push further.

Because she had gotten what she wanted.

Not a confession. Not a confirmation.

But a reaction.

The damage was already done. Even if I denied it, the seed of doubt had been planted.

And knowing Sakayanagi, she wouldn't let me out of her grasp so easily.

As the class settled, Mashima-sensei entered, his pace unhurried. Something was off—no books, no usual teaching materials.

An announcement.

"Good morning, everyone. I hope you all made the most of your vacation."

Nods rippled through the room. I followed suit.

"Good. Today's news leans more toward an opportunity. A two-week trip aboard the school's private cruise ship. Luxury and hospitality are assured."

A trip?

A cruise ship?

I didn't need to hear the rest to know where this was going.

---

Sakayanagi's POV

Mashima-sensei's announcement confirmed my suspicions. A trip this soon after vacation? No, this wasn't a gift. This was the setup for something much more deliberate.

A ship. Open sea. And beyond that—an island.

It seemed Ai's deductions were coming together. Or rather... Sienna's.

Katsuragi would no doubt attempt to use this to further his position, but I couldn't allow that. Our class's success had to be orchestrated by me.

As the lecture concluded, I approached Ai, who was gathering her things.

"Would you mind, Ai?"

She stopped, glancing up at me with lazy eyes. "Homeroom's already over?"

"Yes, it seems so."

I lowered my voice. "I plan to make precautions for this upcoming exam. Though I've given Kanzaki the go-ahead to prove his leadership, it would be wise to monitor him, don't you think?"

Ai raised an eyebrow. Then, with a small smirk, she countered, "Then let's kill two birds with one stone. I'll watch Katsuragi, but let's have Sienna assist me."

I tilted my head slightly. "Sienna? Why her?"

"Because if you're still skeptical about her true abilities, what better way to confirm it?"

Fufufu. Clever. Ai was playing her own game.

Very well. I'd allow it.

"Fine," I agreed. "If an exam does come, she'll assist you."

Ai nodded. "Alright then."

As I walked away, my pace was slow, unhurried. The pieces were aligning. The exam, the suspicions, the players involved.

I wondered... How far would Sienna go to maintain her façade?

And more importantly—when would she break?