Chapter 22: Anti-Ageing

「Inis!」

The next day.
I head to the university with Chryse and call out toward the softly drifting sofa.

「Oh, Sensei, you actually came today. Gooood job.」

Inis, as ever, answered in a snide tone while lazing around, rolling on her sofa.

「I just took a single day off.」
「But, y’know, me—the one people call the Witch of Sloth, me—came to school without slacking off, and Sensei plays hooky? How’s that fair, hmm?」

Yes—utterly, completely the same as always.
I don’t know her exact age, but it’s been nearly seventy years since Inis entered the university. In other words, she’s certainly over eighty.

That’s already quite long‑lived for a human, yet Inis looks exactly the same as back then—like a teenager, even childlike.

She could pass for a baby‑faced elf given how little she’s changed, but she’s human through and through. Her ears aren’t pointed, and I know her lineage well enough to list their names back thirty generations.

「Sorry. I’ve got something to ask you, Inis.」
「Something to ask?」

I nod at her tilted head and say—

「About the anti‑ageing sorcery you’re using.」

Long ago, when I grew suspicious of how little she changed and pressed her, she told me straight out. She even explained the principle then, but it was abstruse and I wasn’t very interested, so I let it slide...

「Sure. I’ll explain. First off, compared to other species, the human body is extremely plastic. That’s called phenotypic plasticity: suppose we have n people and take each individual’s height as x, with the mean μ—then the deviation distribution is given by μ minus x over—」
「Hold it, hold it, hold it.」

As Inis pulled a notebook from the sofa and began dashing off formulas, I hurriedly stopped her.

「What I want to know is much simpler.」

Numbers and theory won’t help—I can’t follow them. I don’t even know how to read the equations she’s writing.

「That’s enchantment, right?」
「Well of course. Enchantment’s my specialty.」

She nodded to my question, looking a little dissatisfied. She may be called the Witch of Sloth, but when it comes to explaining her field she suddenly comes alive. Almost no one can keep up, though—not even her pupils.

「Then how do you explain my longevity—and elves’?」
「...I don’t think it’s the same.」

After thinking a moment, Inis answered.

「When I first set out to make anti‑ageing sorcery, my first idea was to transform an old body into a young one.」

I nod. It’s the first method anyone would think of.

「But as you know, Sorcery reverts when the effect ends. Once it wears off you’re back to an old body, and big changes demand big power. Turning an aged body into a young one—yeah, that’s beyond humans. Elves or pixies... maybe mermaids could manage, with their high mana. Not that elves need it in the first place.」

The strength of magic differs by race. What we call mana has become fairly measurable ever since Sorcery came into being.

「Even mermaids can’t—unless you pay a steep price.」
「A price... Right, that’s another route.」

Startled by my words, Inis sank into the sofa and fell into thought.

「So how do you do it, Inis?」
「Ah, sorry. Um, put very crudely—I strip the body of the function that ages. Then I just reapply it periodically.」

When I prodded her out of her reverie, that was her answer.

「...That means...」
「Exactly. Aging and growth are two sides of the same coin. As long as I’m using this sorcery, I don’t age, but I don’t grow either. Dragons and elves aren’t like that, right?」

I nodded. Elves slow down drastically after a certain age, but they don’t stop changing altogether. Even Nina—who’s counted a thousand years—still changes, little by little.

For me it’s even more pronounced. My human form doesn’t change, but my true dragon body grows year by year. If a dragon’s “year” is ninety‑eight years, I’m only about ten—still in my growth phase.

「By your account, dragons and elves don’t have lifespans, right?」
「Probably.」
「If so, why do dragons and elves grow at all? If they can live on forever without dying, there’s no need to bear children. They could just exist as complete beings from the start.」

I had no answer. I’d accepted it as simply the way things are. If you’re a living thing, birth and growth feel essential. But by that logic, so does death.

「Conversely, if you bear children and grow, then you must have a lifespan. That’s what plasticity is.」

Inis stated it plainly.
Indeed, if a species kept increasing without lifespans, this world would eventually be filled with nothing but that one species. Fire dragons, unlike elves, have no natural enemies. However low their reproductive rate, the end state would still be a world of fire dragons.

If we aren’t seeing that now, is there some hidden mystery at work... or are we simply in an era along the way to that end?

「Um, Inis‑san. The anti‑ageing sorcery you’re using—can anyone use it?」

Chryse, who had been quietly listening, suddenly asked.

「Not yet. I haven’t formalized it. So this isn’t Sorcery; it’s magic.」

We call magic that alters the properties or form of matter and bodies “enchantment,” and converting it into a written description is called formalization.

It’s recently become clear that when people use magic, some of it is controlled unconsciously. But write the spell as text and anyone who triggers it gets the same effect—in other words, the unconsciously controlled part gets stripped away.

The more complex the art, the exponentially harder it is to replace that unconscious control with writing and still get the same result. Anti‑ageing magic is something only Inis’s godlike sense makes possible. It looks like the day Hiiro’s average lifespan soars is still a long way off.

「Even going so far as inventing such advanced magic just to stay with Ara‑kun, you still haven’t confessed?」

In my eyes, Chryse’s guileless question turned into a spear that skewered Inis straight through the chest.

「Wh‑why do you even know about that...?」
「Because I think the only one who doesn’t know is Ara‑kun.」

As Inis forced the words out with a groan, Chryse furrowed her brows, looking rather perplexed.
Setting aside the forty‑odd years ago when she happened to witness Inis weeping in secret, the Chryse of today seems able to fully understand her feelings.

「I‑it’s fine! I still have plenty of time...」

She insisted, but that very leisure felt like it was pruning away her chances. If her time were short, I couldn’t help thinking she’d have steeled herself and confessed already.

「So why bring up anti‑ageing again? It’s got nothing to do with you or with Chryse, Sensei.」
「Yeah—what I wanted to know was exactly that: whether it’s unrelated.」

Inis coughed as if to dodge the point, and I nodded.

What counts as a mystery, and what doesn’t? It’s a hard question.
Is it something that lies on the extension of existing technique, or an endless wonder?

If you want to check, the quickest way is to ask whoever stands at the very frontier of current technique. As far as I know, that’s Inis.

「...I don’t really get it, but will that fix whatever you’ve been brooding over lately, Sensei?」

Oh. So Inis had seen through me too. Apparently I’m easy to read.

「Well, this won’t solve everything. There’s someone else I have to hear from. They live a little far away, though...」

To my knowledge, Inis is the sorcerer who understands modern technique best.
But the one who probably holds the widest knowledge is someone else.

「Isn’t it in Hiiro?」
「No.」

I nodded to Chryse’s tilted head and answered,

「Back home.」