Mamonaka Miyao was a girl in the volleyball club and stood a full 180 centimeters tall.

She had a toned body, excellent looks, and not only in volleyball but in gym class too, she showed outstanding athletic ability. I had even heard rumors that girls had confessed to her.

She was a beautiful, cool female student who made those rumors easy to believe.

And it was not only her height that was large, but her chest too...

But right now, more important than that was the fact that she had said she wanted to become one of our companions.

Ms. Luminous and Shoubu had already become companions today, so I had not expected a third candidate to appear.

Day Nine was turning out to be incredibly dense.

“When you say you can be useful, what do you mean?”

For now, I asked on everyone’s behalf.

“U-um. My ‘transformation ability’ lets me transform into living creatures I’ve seen before, so I can become all kinds of creatures depending on the situation...”

“Does any living creature work? If you can become a lion or an elephant, that sounds amazing.”

“Y-yes. If it’s a creature you’d see in a zoo or aquarium, I’ve seen it before, so that’s fine. And I can transform into monsters too.”

“Monsters too... Then the more monster types we encounter from now on, the wider the range of your ability becomes.”

Minori murmured, sounding impressed.

“An aquarium means you can transform into sea creatures too? Dolphins and turtles and stuff?”

Shouko spoke up before she could stop herself.

“Huh? Yes. I can, but...”

“Ooh...”

Shouko seemed moved.

Flying through the sky like a bird or swimming through the ocean like a fish was something everyone dreamed of at least once. Maybe knowing that Mamonaka could actually do that made her feel a little envious.

“...Then what about phantasmal beasts?”

At Yumekai’s words, Mamonaka paused for a moment, then nodded.

“Shouko’s summoned beasts? The ones I saw just now? It seems like I can transform into them.”

“Seriously? Myao, that’s amazing!”

Shoubu cried out in surprise.

“‘It seems like’?”

Something about the wording caught my attention. Mamonaka looked like she was trying to figure out how to explain it, and after a few seconds, she attempted an answer.

“It’s like... when I picture the creature I want to transform into in my head, I can tell whether it’s possible or impossible. If it’s a creature I know about but haven’t seen, then I can’t transform into it...”

“I see. Since you’ve seen a Fenrir and a black dragon, Mamonaka’s ability judged them as ‘possible to transform into.’ Is that it?”

“Something like that...”

Still, Mamonaka had been acting strangely for a while now.

She would not meet my eyes. Her face had also been red the whole time.

...Could she be embarrassed about what happened when she was a cat?

That cat had been strangely attached to me, but all those adorable actions had actually been Mamonaka’s actions.

I did not know her true intentions, but when I imagined how she must feel after thinking she would not be exposed and then being revealed as a person, I could understand why she could not look directly at my face.

Once I thought of it that way, I started feeling embarrassed too.

“...If that’s the case, then this changes things. Shouko has summoning ability, but it’s not like she can summon multiple Fenrir-class beasts, and I think Myao would be useful if she can switch between all kinds of living creatures.”

Yumekai had voiced a slightly strict opinion earlier, but after hearing about Mamonaka’s ability, she seemed more positive about letting her join.

Right now, Shouko was just barely unable to summon her third phantasmal beast.

Even if she became able to summon a third, having Mamonaka effectively add one more beyond that would be a plus for the party.

“Myao, can your ability transform other people?”

That question came from Shion.

“No. At least, I can’t do that right now.”

“Myao, what about partial transformation?”

At Chiyu’s question, Mamonaka tilted her head.

“Partial transformation? Um, you mean like a manga character, changing just one arm into another creature’s arm or something?”

“That too. What I want to ask is whether you can become a real cat-eared demi-human.”

Chiyu’s face was expressionless, but she radiated pressure, leaving Mamonaka bewildered.

“............I-I think I can. But of course, I can only reproduce traits of living creatures I’ve seen before.”

“Mm. Accepted.”

“Chiyu, don’t decide that by yourself.”

Also, why was being able to grow realistic cat ears the deciding factor?

Well, as an otaku, a cat-eared demi-human was something I did want to see at least once.

“I understand that Mamonaka’s ability is useful, but why do you want to join Sousuke’s party?”

That part seemed to puzzle Minori.

Since she said it after seeing our base, it was possible she had simply been moved by our high standard of living. But she had contacted us back when she was still a cat in the first place.

If she had wanted to become our companion even then, maybe there was another reason.

“Th-that’s, um...”

Mamonaka glanced at me, then immediately looked away.

“Isn’t it because Myao likes Kuno?”

At Yumekai’s exposure, Mamonaka panicked.

“W-wait, Serina!”

...Come to think of it, Yumekai had seemed convinced when she learned the cat was actually Mamonaka.

“Huh? Really? I never heard anything about that.”

“I didn’t know either.”

“Me neither. Actually, why do you know, Serina?”

It seemed even in Shouko’s group, only Yumekai had known.

...Or rather, I had no memory of this either.

“There’s no point hiding it now. In our first year, some boys had a really awful conversation within Myao’s earshot, and Kuno casually solved the problem.”

—I-I didn’t remember that...

But it was true that Mamonaka and I had been in the same class in our first year too.

“It’s not that I like him, exactly. I just thought he was a good person...”

Mamonaka said it while fidgeting and tangling her fingers together.

So that was why she had been friendly when she was a cat.

“...So-kun, did you actually set up quite a few flags back on Earth too?”

Chiyu’s voice sounded a little surprised.

Her tone was still flat, but as her childhood friend, I could tell how she felt from the tiny changes.

I would never have realized it if we had not come to this deserted island, but apparently there had been more people than I expected who already had positive feelings toward me back in Japan, like Shouko and Minori.

Now Mamonaka had been added to that list, so I understood why Chiyu was surprised. Or rather, I was surprised too.

“Kuno, that really is admirable.”

Ms. Luminous looked happy too.

She seemed impressed by the part where I had helped a female student in trouble.

“As expected of you, Master.”

Roa praised me without missing a beat.

“S-so... what do you think?”

Mamonaka looked at us anxiously.

“Honestly, just being able to transform into phantasmal beasts like Mashiro and Micron seems like a really incredible power. If you understand how this party works and still want to join, I think it’s fine. What about everyone else?”

No one objected.

“In that case, welcome, Mamonaka.”

“Th-thank you...! I’ll do my best!”

Mamonaka agreed to our conditions too, including not returning until everyone had a Right to Return, and waiting until those who wanted to could carry over their abilities and memories.

When Chiyu said, “Joining So-kun’s harem is also an absolute condition,” Mamonaka turned bright red and looked down, but I immediately told her, “Don’t worry about that,” so it should be fine.

It would be a lie to say I had no interest as a guy, but I had no intention of forcing anything.

Chiyu had probably said it because she thought things would hold together better that way, not because she was absolutely determined to make me build a harem.

Or so I said, but I already had three girlfriends, Minori was scheduled to come to my room tonight, Roa had served me, and I had seen Shoubu without clothes...

In any case, that was how our tenth companion joined us.