"And a key to a room, if you please?"

Room 2089, says a napkin accompanying a key.

"So, uh, that was my parents."

"Yes. They seem nice."

"Yeah, I think so. Dad sorcers professionally and Mom's a genetics professor."

"What sorts of practical applications do professional sorcerers find there to be call for?"

"A wide variety of things. Sorcery can do a lot of stuff that current technology just can't, and some stuff that it can, more cheaply and effectively."

"Sure, but, typical day examples, I wanna know what to get excited about."

"Over the past couple of weeks Dad's been called on to demolish a condemned building, move a tree that couldn't have been mundanely transplanted without killing it, immobilize a broken leg bone so the kid didn't have to get a traditional cast, and clean out a chunk of lake that someone had been dumping garbage into. Last month he and a couple of others worked together to renew the city's darkscreen. Um, that's a one-way shield over a city that prevents the light pollution from getting out and confusing bats and birds and stuff. I guess you don't have those, huh."

"We do not have those. Couldn't heal the leg outright?"

"Theoretically could have, but--Dad's not really a great healer. He's better than nothing, but for something like a broken leg you want to go to a specialist who'll make sure you won't be feeling rainstorms in it when you're sixty. But specialists like that often have waiting lists, so the kid had to do with a magical pseudo-cast for like a week until he could get to one."

"Makes sense. What exactly affects whether someone's a good healer or not?"

"Skill, inclination, personality--other stuff. Short version is Dad isn't one because trauma. He's--actually really good when it's an emergency, his mind goes sort of cold and clear, and he can do some damn impressive stuff when he's like that--Mom doesn't even have a scar, and she got shot in the lower spine once. Which...was kind of a good thing, actually, because when sorcerers and artifact users associate a particular state of mind with a magical action too much, the magic can start feeding back in on it and creating a loop. The clear cold thing sort of kicked him out of the one he was in. ...I didn't think it was relevant because it's really, really rare, and frankly you're...pretty much the opposite of the kind of person it happens to. Your notebook thing, specifically," she clarifies. "It's the kind of thing that happens when you don't pay attention to your emotions even as much as normal people do, most of the time."

"I pay attention. I don't let them get out of control."

"Yeah. He was pretty much only vulnerable to it because he was in a really bad place mentally at the time. I--still should have thought of it. And told you."

"Tell me more about the loops?"

"They happen when a sorcerer or an artifact user has a specific strong emotion, and feeds that emotion into the use of magic--the way you'd feed anger into a punch, basically, or joy into a dance or affection into a kiss--on a regular basis. And then you start feeling that emotion a little more often, in a way that makes you want to do magic with it, and then that makes you feel the emotion more often, which makes you want to do more magic with it, and this basically usually ends either with you snapping out of it and being careful about doing magic while feeling that emotion for a while, your friends knocking you over the head and dragging you to a therapist--I'm being metaphorical here--or dressing in melodramatic cloaks and hiring henchpersons and getting thwarted by other magic users. If it's a negative emotion, anyway, the worst that happens if you feedback on a positive emotion is that you get annoyingly chipper, but positive emotions are harder to let get out of control anyway."

"...I'm sorry. I keep forgetting important things and I don't know why."

"It's okay. I'll keep a handle on it. And your dad should have mentioned this, too, it's not all you. And I would have asked but he surprised me, which is not your fault. Anything else I should know?"

"Not off the top of my head. Give me five minutes to think about it."

"Okay."

"...Okay," she says after a few minutes. "If for some reason you're ever in my world, some magic users can tell various ways if you're a sorcerer or not, and some villains prefer to target them specifically--usually 'join me or die' kinds of things. Don't try healing someone with a spell you're not sure you have down unless it's enough of an emergency that fucking them up even worse won't make much of a difference. A sorcerer spell, I mean, so far as I can tell magical girl spells don't have failure modes like that. In fact, don't do any spells you're not sure you have down unless damaging the target is an acceptable outcome. You can practice spells in your head without actually casting them. If you have a spell down but you think you'll have it down even better later you might want to wait--fixing something perfectly that's been fixed imperfectly is much, much harder than fixing something from normal broken."