"You can use any magic you like on my eyes, unless there's a risk of damaging some other part of my body."

He guesses the doctor is allowed to know then? "Hello Doctor Shor. I don't want to try that yet. I've been learning about eyes already from Tanno and they're complicated. There's different kinds of flesh in them, and tiny blood vessels, and muscles, and stuff. I still need to use sensing magic on people with good eyes and bad eyes for a while. I used it on myself and on miss Larian and I think it's mostly that my eyelid is stuck to my eye, and the 'cornea' is damaged. It can be really bad to mess it up. I wanted to help with your burns today, that's all."

"Oh.

Okay. I've been eating and drinking."

"That's good. Are you okay, though? I thought you were the same age as me. The Magistrate told me a lot of things. I'm kind of mad, but also it makes sense. People never tell kids everything important. It makes me pretty mad. I'm still kind of mad at her. But I'm definitely going to try to heal you anyway since you want that. No more pretending when you don't have to please."

"I was supposed to be about nineteen*, actually...

I'm fine. I didn't ask you for healing. It would be nice, but I'm fine, there will be taddies for me to teach, and I have plenty to think about. Like why hotter steel glows with a different color than colder steel - why do hot things glow at all.

I'm not going to lie to you anymore, but I don't want my real age getting out. Do you know why people don't tell kids important things?"

* ten in Earth years

"I meant a kid like me, not exactly the same age. Fire is hot and glows... I know there's more colors we can't see but some animals can, my f-friend Lenora wanted to get four colors eyes from the doctors but was too little... I think you have to do experiments to figure out new things. And I want to heal you anyway. And no, I don't know. Why do you think they don't?"

"And why does fire glow? Light has energy - it can heat things up - but why do all hot things make light? If it was just fire, we might say that light is a substance released as the fuel is consumed, just like exhalation. But all hot things make light. Catfire makes light and heat, but doesn't consume fuel or vitality and doesn't produce exhalation. Is heat the same substance as light? When light shines on an object frozen by an aasimar, it reflects back and it heats up the object and can even make it glow, but no amount of light will burn the object. What is color: different speeds, different sizes of droplet? Or is light a movement like sound, with different pitches? That would be elegant, but then it should just reflect off a frozen object, and shouldn't be able to travel through the emptiness between us and the stars. Unless there's something there after all, something that stays even if you grab the air?

Anyway.

Nico, do you know how to obtain different colors of light, other than with a prism?"

"You can burn things to make different colors! Maybe different things vibrate differently, like different strings on a harp? Or maybe they hold different sized droplets... Like you have to heat up water a lot more before it feels hot, compared to steel. So water holds bigger droplets of heat?"

"That's something we can test!"

Yay she did a smart cat thing.

"...Only with magic. I know there's a kind of light that's called, um, below-red I guess, and when things get hotter it shines that before it shines red. And there's after-blue, which the sun makes a lot of and can burn you, and REALLY hot things can make. Does fire make the same amount of light as something that fire made hot? I think it makes a lot more? What other things make light? Do frozen things cool down again if they glow hot? We can drop hot metal and hot rock into a big bowl of water and see how hot it makes the water! I think a lot of the heat would just escape though. And I don't know how to measure how hot something is, just if it's burning or not?"

Yes she knows about colors that frogolds can't see, and he already said that just 25 seconds ago, and she's grumpy that he knows more about eyes than she does. This should be an opportunity to learn but she doesn't feel like it.

"The same amount of light relative to what? The light comes from the whole flame but only the surface of hot steel.

Some bugs make light without getting hot. Frozen things cool down. I don't know a precise way to measure temperature but you could probably use how stuff expands when hot somehow."

"At the mill we just look at the color, or touch it."

Doctor Shor speaks up. From the location and timbre of his voice he's a frogold. "To check the temperature of a person, we put a piece of metal in their mouth for a while, rinse it, and get someone of the same species to put it in their own mouth and say how it feels. But that only works for temperatures right around what their body is supposed to be at."

"Two high-pitched whistles make a third low buzz. Does light have the same effect? Two sounds of almost the same pitch wobble in volume. Can we make a flickering light that way?"

"Huh, sounds do that? Since hot things glow maybe we could figure out temperatures from the color..." He sounds doubtful. "I think you need to measure things to do experiments. These things are hard to measure. Sound shakes things, maybe we can measure it with a thin piece of paper that shakes?"

Yeah she's doubtful too. How do you tell when the tiny piece of paper shakes?

"Hmmm..." She pretends to settle in for sleep.

"Let's give her some rest."

The tengu shuffles over. "Nico, question from the Magistrate: do you want to stay secret longer than the five cycles you discussed?"

"...I want to stay secret longer, yeah. Until I learn how to do lots more magic."

The tanner is released, having apparently committed unlicensed counter-disiniuria, with the fine waived for his heroism.

Quiet Pavel stops by, saying that he's going to the new town, Embal, for a few deci-years, but he'll be back, so "take care of yourself, kid, you have lots of friends, and keep up that Kef spirit!"

Nico does not get invited to draw guides for the turbines in Embal, but the new aqueduct is running soon enough. Doctor Shor complains that the water in the Kef aqueduct is cold. "We knew that would happen eventually, of course. There's no reason for the water from Kef to be heated so far above freezing - that was always a temporary state in preparation for the additional incoming cold water - but we're lucky that Kef was ready to accept the frogold district before it happened, since now we can openly sell fish and reeds to pay for heating our pools."

The missing fire crew catfolk are okay! Apparently they were hiding with the frogolds.

Nico sulks and hides a lot in the next few days. No more illusion shows, not really talking to his friends or new family either, except for asking everyone who knows about his magic except the Magistrate herself if he can look at their eyes with Diagnose, for an extended duration if they'll let him. Tanno doesn't want to risk it, even with cleverness like carefully extending his foot down and having Larian push his breath upwards.

Eventually, after literally forever (7 days total), his impatience at being blind outweighs his terror at getting it wrong and living out all the horror stories of healing gone badly. After eating a good meal and letting it digest for a bit, holding carefully in mind exactly what a healthy eye looks like - shape, iris, cornea, blood vessels, nerves at the back - and what his eyes look like, and the lye that damaged them, and slowly pushes everything back into the right order and shape.

It's itchy. He focuses on it for long, long minutes, until... There's nothing left to repair. He opens his eyes, then squints them shut again against the brightness. It... Works?

Part of him didn't think it would actually work.

He stares at everyone from the tengu to Calsa and Merta and Siki for a while, blinking and getting used to seeing again. It's only been a few days, but it feels a little weird. Do things look a little bit blurry? Maybe. He can't really tell. And it doesn't really matter because he can see again and doesn't have to stumble around unable to tell what's two inches in front of his nose.

He will hug Calsa a lot.

...And then offer to go try the same thing for Lin. Tomorrow. When he has his green magic back.

"I appreciate that you want to heal me.

What will I owe you? Don't say nothing, because it's not nothing, even if you can't measure it in metal or money."

"I know... It's actually a lot. I think you know how to fight people? I think it would be good to learn that, but only from someone who doesn't want to hurt me."

"Okay, I'll teach you to fight!"