Blond Luke, dark-haired Derren, downy-brown Jake, and black-haired Max. Four adult guys (Aunt Delilah had moved on to a world tour with the kids grown up for real) and all of them dynamists. Alchemists who viewed magic-things in terms of shifting energy and change, bodily form was a...flexible consideration. And if they wanted to change things around with each other, they probably would.
"Welcome to town, Jake!" Max said. "Same contract as usual, full month change-for-change with each of us then reset?"
"Sure." Jake agreed, relieved at the wash of subtle agreement-magic. He dumped his stuff inside and closed the door, prepared for anything.
It was a bit of a game they played to ensure no harm no foul about changing things up for the visit, and revenge could be handled on the spot for fairness (or exploitation). Each time they transformed someone, that someone gave them a new transformation back (not looping, but if they added a second onto that it'd be a new reply), and everyone (and thing affected, given certain reality impacts) would be reset when things finished up, except for if their unaffected selves wished to keep those parts. Sure, they could transform back if they needed to do something, but beyond that while they were together show off the imposed style. Jake had spent a fair share of weekends and vacations growing up as a thick well-shaved farmboy (and sometimes an idiot), and Max's side of the family had spent plenty of the others as highfalutin nobles (and sometimes as nerdy gaming partners), but they'd all been relatively leisurely younger than this and had been waiting for an adult reunion to get serious. They'd texted a bit before this, outlining most of the details, but the short of it? It was going to be a shameless romp in bed most of the time and messing around the house most of the rest.
"So, who wants to go first?" Max asked politely, causing Jake to pipe up.
"Alright, you three are gay now," Jake said, "like me, and like the plan. And not just 'reserved shy library boy' gay (yet), I mean raging horny homosexual gay, buff or sissy or whatever's your pick, just be ready for incest. Pick your retaliations, gentlemen."
"A bold opener." Max said, chuckling and patting his bulge. "As much as I joke about your hair, you could use some weight. Take your clothes off and muscle up for me, about twenty pounds or so should do it. You look better when you're not so twiggy."
Shucking shirt and shorts alongside shoes, Jake comically flexed as he gained a bit of muscle definition.
"Hear me out: small dicked top." Derren cut in. "Don't have to go micro, but gimme something that'll be gentle and easy to swallow. High sensitivity's usually a perk when I'm gay so roll that in too, but count it as a full second change if you want."
Confidence cut down, Jake rolled his eyes, crossed his arms, and let the others watch his dick compress into a sensitive thing about the size erect of some men flaccid.
"Cute, but the contrast needs more work." Luke said. "For my retaliation add some fat to soften that tone, and as extra put on some glasses. Comedy nearsighted deal so they stay on during sex unless you wanna make blindfold jokes or something, you could go for a power nerd look."
Patting a belly that suddenly bulged out a bit and adjusting squarish new lenses, Jake smirked and threw on the counterattack. "Okay, Derren, your dick is now big. Not like hyper overkill, but the size soft some people are hard kind of deal. Luke, you're constantly horny, like have a boner unless you're doing something else horny."
Derren unbuttoned his enlarging pants to show off the impressive tool behind the bulge, and Luke just started masturbating with a hand down the front of his pants because why not.
"A splendid opening all around." Max said, not concealing the boner he was sprouting at the men around him. "We'll see how this goes."
Ideas for changes sprouted in each guy's mind: this was going to be one very fun month of free stuff.