An eleven-year-old boy that looks substantially less stretched opens the door to that particular compartment. "Mm mhh," he says around the chocolate frog filling his mouth. He drags his luggage in without waiting for an invitation and finds somewhere to put it while he works on chewing and swallowing the chocolate. "Older kids are cool but they don't think young kids are cool and all the other compartments only have older kids." He flops down onto a seat in front of the painfully bored boy. "I'm James," he says, and extends a hand.

He has a noticeably American accent.

"David," says the stretched-out boy, tucking his arms into his sides as his wand vanishes up his sleeve. "I don't... shake hands. But it's nice to meet you. Are you American, then?"

His accent is plummy and elevated, but his clothes have the shiny, thinned-out look of too many cleaning and repair charms.

"Born and raised there, mostly. But moved here a few years ago. Why don't you shake hands?" he asks, withdrawing his own hand. He reaches into his robes and grabs another chocolate frog, still in its box. "Want one?"

"Sure!"

He plucks the box from James's hand and unboxes it, his hands moving precisely and giving off the faint impression of a very large praying mantis. "I don't shake hands because I have a debilitating magical condition that causes... you know how in the winter, sometimes you'll try to touch something and it'll shock you? It's a bit like that, but worse. Not a good first impression."

"...well now I wanna try it! Unless you mean it's bad for you? But I'm curious."

He fetches a second (third?) box from his robes for himself.

David extends his left hand wordlessly, his right hand holding the chocolate frog by one unmelting foot.

Ooh cool! He extends his left hand there.

And as their skin connects -

electricity isn't like this. Fire isn't like this. Magic is like this. Not the nice domestic magic James has been surrounded by his whole life, but raw, untamed magic, the stuff that creates and destroys and ruins and reshapes.

It fucking hurts.

It's over after a second, as David snatches his hand back, hissing. "...stronger than usual," he notes, then bites the head off his chocolate frog.

James flinches and blinks but doesn't immediately pull his hand away. Instead he looks at it for a few seconds, then says, "Coooool. Can we do it again? —I mean, if you're cool with it."

Definitely from New York.

David swallows hastily before his incipient giggles can give him a coughing fit. "Cool with it. Was a bit rich for my blood, honestly, but maybe I'll prod you again at a later date. Perks for good behavior."

He bites off a leg and lets it sit on his tongue a bit meditatively. "Most people regret it. Even the aurors - 'specially the aurors, really."

"Why does it happen? What is it? Can you make it stop, or stronger? How do you kiss girls with this? —or boys if you like boys."

"Don't know why it happens. It's basically just magic buildup that reacts with somebody else's magic, far as anybody can tell. I can't make it stop but I can make it worse if I try. And, I typically don't."

"How much worse?"

"Hard to quantify. I learned some truly dire words from the Auror who tested it, though."

"'Truly dire'. I wanna teach you new words, too!"

There's a hum. The air feels somehow thicker, more present. David pokes James in the forehead.

It isn't the Cruciatus. It's got that going for it. But it feels like something fundamental, something foundational within him, is being burned and blasted and ripped apart inch by inch. It spreads through him, like molten iron in his blood, for what feels like much longer than the few seconds it takes for David to withdraw.

"One of these days I suspect you're actually going to regret something," David says, shaking out his hand. 

Okay this time he pulls away and falls over.

He does however straighten back up and grin widely again. "I wanna learn how to do that!"

"Well, I'll tell the research healers to get right on figuring out how to inflict it on people. They so rarely get to do that, you know, people usually want things cured."

"Well I guess it would be good if you could figure out how to stop it. At least sometimes. Kissing people is nice."

"So I'm told."

An extravagantly tiny blonde child wearing muggle clothing and a military surplus rucksack opens the door and clambers in. "Hello hello - may I sit here please, you seem friendly and I would not like to sit in an empty compartment -"

"I can't imagine a more conveniently sized fellow traveler. Feel free."

"Would that make you inconveniently-sized?" he asks David before turning to the tiny one. "Hello, I'm James."

"I am manifestly inconvenient. And my name is David," he adds to Tintin.