"Huh. Are there living things this noticeably affects?"

"Sure. Plants where there's still uncontrolled plants are a little improved. It's a little harder for animals to breathe, which turns out to make people measurably dumber."

"Huh."

"We are trying to puzzle out why in the future there's nothing visible of us."

Nod. "Is there a way to test whether we're affected by carbon dioxide?"

"In specifically the being dumber way or in general? I mean, I can make it just fine."

"I mostly meant in general. Do please test it on someone else, I don't want to be dumber. There're prisoners."

"I am going to predict that that's considered horrible by civilized society."

"It's temporary. But also that, yes."

"I don't have a model."

"They wouldn't have agreed to it and it's not absolutely necessary to keep them contained at all. It's approximately that simple, except for the sex thing. I feel like you might've gotten a wrong model of how complicated most of it is because it's so complicated in that one place."

Nod.

"Some of the perceived complication of the sex thing might just be different expectations about what people'd agree to."

"I -" he glances at his brother. 

"You should say that but not now."

"Maybe that's it and eventually I'll have a one-sentence explanation of that for everyone else too," he says after a second.

Cam looks between them, confused, but doesn't ask.

"Do faeries have the same taste in food as humans?" he asks, taking a meringue.

"Not dead on, I think you don't gravitate as much toward calorie density and you're also more likely to be pleasantly surprised by weird tastes you haven't encountered before, but you sure seem to like things humans find tasty."

"Is this possible to make in any way other than magically?"

"Meringues? Yeah, you beat egg whites and sugar and probably other stuff plus whatever you want them to taste like and... I think they get baked."

"Awwww. Tragic."

"That one can make them without magic or that they get baked? You could probably eat it raw too if you don't get food poisoning from raw egg, it'd just be wet or something - I don't know, I've never personally baked meringue."

"The baking, because we can't do that. Maybe eventually someone'll invent a way. Do humans get sick from eating raw eggs?"

"If there's germs in the eggs, not inherently, but cooking them kills the germs."