Monday.

Minaki Suzu, who arrived early at school, quickly checked the classroom.

A half-locking mechanism had been newly installed on the windows to prevent fall accidents.

This must be the “minor construction” mentioned in the class meeting.

Looking around, she noticed that the power outlets also appeared to have been replaced.

There seemed to be other changes too, but at a glance she couldn’t tell. She decided to head to her seat.

Then she accessed information on Toudou Mizuki via her smartphone.

His pairing count had been updated from zero to two.

“Whoa…”

And just like that, her remaining concern—that he might have a problem with sexual function—was gone.

She thought over the “two pairings”.

(It’s common for someone who assists once to end up in a pairing… but who was the other girl?)

She ran through a few candidates in her mind.

At that moment, Kaminari Nene entered the classroom.

Her expression was somewhat brighter than usual.

“Good morning.”

“Yo.”

Only a few students were in the room.

Suzu stood and made her way toward Nene’s seat.

“Looks like you pulled it off.”

“Y-yeah. I think I did okay.”

As they spoke, Suzu glanced at Nene’s fingers. A red ring gleamed on one of them.

There is a concept called a colony.

Separate from the marriage system, it refers to a group that has sexual relations with a particular man.

A colony carries no special legal restrictions, but in general society, it frequently carries great meaning.

Once someone joined a colony, they were expected to avoid contact with other men.

This served not only to prevent competition between colonies for men or women, but also to stop the spread of infection from one colony to another.

The independence of each colony was epidemiologically very effective—and had been recognized implicitly throughout human history.

The red ring Nene wore signified she had had a first-time and thus belonged to some colony—a kind of aspirational accessory.

“…Isn’t Toudou said to be bad with women?”

“Y-yeah. He wasn’t good with them up through middle school, but now he’s fine.”

“…Huh.”

Probing lightly, Suzu thought it strange.

She couldn’t believe a woman-phobia could just disappear so easily.

And the fact that his count had gone from one to two weighed on her mind.

(So, someone must be behind this after all.)

Just then, Aihara Yura walked into the classroom.

“Good morning!”

“Yo.”

Yura went straight to Nene.

“How’d it go!?”

“Uh… I think it went fine.”

“Nice! Congratulations!”

Suzu watched Yura cheer sincerely and felt a little impressed.

That was a precious trait at Shirayuki Academy.

“Oh—already got the ring on! Did you buy it?”

“I rushed out and got it Sunday. I don’t want anyone but Mizuki-kun to touch me.”

“That’s like something out of a manga. I want one someday too.”

As they talked, more and more girls arrived.

“Good morning, Kaminari-san. How was it?”

“Um… nothing special, I guess.”

Slowly, other girls who hadn’t had relationships before began to gather around Nene.

(Well, this is how it goes.)

The other girls were likely thinking about “set sales” too.

Since this was Nene’s first assistance, she had a high chance of becoming his favorite. If that happened, those near her would also get opportunities.

“Good morning.”

Houjou Noa’s voice cut through, tightening the air.

Suzu froze.

Not just her—everyone in the classroom stared blankly.

“Kaminari Nene, I heard your assistance worked out. Congratulations.”

Houjou Noa spoke politely, her hair up and hair accessory in place.

Her usual princely air was gone; she now presented a decidedly feminine silhouette.

“…Ah, thank you.”

Nene looked up at Noa in surprise.

Noa ignored the stares, then headed to her seat.

“Noa-sama! Your skirt’s too short!”

“Isn’t this normal?”

Shinonome Yukari complained disapprovingly, but Noa paid no attention.

(Maybe I should go back to black.)

Suzu touched her hair instinctively. The golden highlight she’d added—so she wouldn’t be underestimated because of her height—caught her attention.

If Mizuki-kun preferred someone like Nene—serious and gentle—then that would be one of the first things to fix.

(Well, it’s too late now.)

Even surface changes would eventually show flaws.

Besides, she felt she’d just blend in among the other girls.

“Good morning.”

“Good morning!”

Mizuki walked into class, surrounded by the greeting girls.

Only Nene greeted him quietly as he sat down.

“Good morning, Mizuki-kun.”

“Good morning, Nene-chan.”

Even as he sat next to her, there was no nervousness. Today his back was straighter than usual.

(…He’s taken a liking to her more than I thought.)

Everyone had probably noticed the change in how they were addressed.

And right after Mizuki sat down, Nene moved closer to him.

Just seeing that, it was certain—they’d become a couple.

“Take your seats, everyone.”

The homeroom teacher entered.

Suzu made her way to her seat, then turned and looked back.

Among all the changes in the classroom, only Isshiki Shizuku remained unchanged.

◇◆◇

“Alright, what have you found out about Toudou Mizuki?”

At the girls’ bathroom during lunch break.

The class-A class rep, Nanase Hikari, questioned her gathered classmates.

“We conducted interviews with his old classmates and homeroom teachers. It’s pretty clear the diagnosis of gynophobia is correct.”

She hesitated a bit before continuing.

“Last year, he was involved in a traffic accident. That… might have caused it.”

“Are you sure?”

“There’s record of it.”

“Find the hospital records and the driver of the car. If there’s any link with Isshiki or Houjou, report it.”

“Damn…” Hikari cursed under her breath.

She couldn’t find anything associating Isshiki Shizuku or Houjou Noa with him.

The Ethics Surveillance Bureau didn’t seem to have reached any real evidence either.

“All that remains is proof. It must be a falsified diagnosis. His pairing count jumped to two with the mandatory donation—it’s just too convenient.”

“But I heard his assistant also got a ring.”

“That’s just a bluff. Why the attendant now? Dumping the application onto someone else has happened before.”

“Listen up,” Hikari glared at the other girls.

“Toudou Mizuki was apparently famous for his looks since elementary school. His info is out there online—just not enough for the Bureau to act. He must have been marked by several influential people long ago.”

“But still—there are no traces of Isshiki or Houjou anywhere…”

Hikari looked around at the others and confirmed the friend doing outside surveillance was fine.

“…I traced Mizuki-kun’s middle school classmates. Bizarrely many came from Kyoto and Osaka.”

“Kyoto, you say?”

“When I looked it up, all of them moved to Tokyo in sixth grade. They didn’t join his elementary school—he merged into a different school for middle school. And in middle school they naturally came into contact with Mizuki-kun.”

“…”

The girls from A-class became silent.

“I believe both Isshiki and Houjou merely took advantage of the situation. Re-investigate any links with the Kyoto aristocratic houses or court nobility.”

The moment the word court nobility was spoken, several girls looked fearful.

Even though the old powers had lost real influence, more than fifty dōjō-ke (noble houses with imperial registration) still existed in Kyoto and retained influence in many fields.

If it were just a local noble daughter, hesitation would be natural.

“…I’ll make them regret mocking the Nanase house.”

The Nanase family had gained its name by restoring order in the chaotic final years of the last shogunate.

As one of the ruling Eighteen Houses, they controlled the police authority.

Even as a fourth daughter, Hikari bore the pride of Nanase Hikari.

“Under my watch, I won’t let the relics of an old era run wild.”

Back in class, the A-class boy—

“It’s time for work,” said Kichijouji Susumu. “From now on, we’ll prepare the monthly mock test. Outsource it if needed.”

“A mock test?”

“For the genetic-donation assistants, each month, we’ll pick the top-scoring volunteer.”

The girls nearby let out high-pitched cheers.

“Can we proceed with that?”

“For the sports festival likewise—we’ll allow high-achievers to accompany the summer donation.”

“Noted. We’ll announce it.”

Kichijouji never looked at Hikari. His piercing gaze remained fixed on his laptop screen.

He was always working on something if idle.

In his relentless pursuit of orderly rationality, Nanase Hikari couldn’t shake her feeling of discomfort.