When Simon wakes up, he can tell something is wrong. Different. It isn't that he's in Jayne's bunk – that's wrong on some levels, but it's hardly unusual, these days. It isn't that he smells of sex and Kaylee's strongest distilled alcohol. He's been in this position before.
He does a mental inventory.
Flattened by the weight of Jayne pressing down on him: check.
Thinking about waking Jayne up in a very polite – and dirty – way: check.
So. Everything is normal. Except that he's fairly certain that when he'd fallen asleep, Jayne hadn't had breasts.
He closes his eyes, wondering if it's a dream. A hallucination. Something that will go away.
When he opens them again, Jayne has shifted, and yes. Those are definitely breasts pressed up against Simon's chest.
"Jayne," he whispers, shaking a shoulder that is both brawny and feminine. "Jayne. Wake up?"
"Wha?" Jayne's eyes are bleary, but Simon hardly notices because he's staring at the curve of Jayne's jaw. It's familiar, yet not.
Intellectually, it's intriguing. "Jayne. Were you by any chance born and raised on Muir's third moon?"
"Huh? Yeah. So?"
Simon gestures, because it's still too early to talk too much. Jayne looks down, and frowned. "Ah, hell. Didn't think this was gonna happen for a few more years yet."
Simon closes his eyes again, nestling back into the comfort of the bed. "Jayne isn't a girl. You said that once."
He can feel Jayne shrug in response. "Was true, at the time."
Every terraformed world has its own peculiarities, and its own effects on the human body. Sometimes it means an illness, or a condition pervasive in an entire population. It might mean that a perfectly ordinary flower suddenly develops hallucinogenic qualities, leaving some townships more paranoid than others. Sometimes water has to be filtered ten times to be drinkable. Sometimes it leaves a body with a prevailing sense of wellbeing.
It's all the luck of the draw, although it isn't a coincidence that the more populous worlds ended up with the most innocuous terraforming peculiarities.
Simon sits on the bed, half-dressed, and watches as Jayne tries to get into his old clothes. It's only half-successful. The pants fit around Jayne's hips – almost – but they're just a little too wide for his waist. The t-shirt doesn't look too bad. "You're going to need clothes."
Jayne looks at him. "I ain't goin' clothes shoppin'. 'specially not with Kaylee."
Simon suppresses a smile. "No. I can't even begin to imagine what she would try to put you in." He pauses for a moment. "Pink."
"Ribbons," Jayne adds, as he buckles his – her – gun belt.
"Teddy-bear t-shirts," Simon continues, starting to feel a little hysterical. He knows he shouldn't be surprised. Every first-year medical student knows about Muir's third moon. It's spoken of mostly in whispers, because the Alliance resents the paperwork that accompanies the phenomenon.
"I ain't wearin' anythin' like that."
Simon nods, "Maybe Zoe would have better suggestions."
Jayne grins. "Yeah. Good idea."
Muir's third moon has a special particularity. In approximately 13.75% of the population, the planet's atmosphere sometimes leads to a certain – ambiguity. The mechanics of it are complex, and ultimately, boring, except to a handful of specialists.
The average person only has to understand three things:
First, some of Muir's citizens sometimes spontaneously change sex. This typically happens in adulthood, before middle-age. The entire process doesn't happen overnight, although only the most observant would notice the initial signs. For all intents and purposes, the most obvious signs often do happen overnight.
Second, the atmospheric particularities trigger a set of genes that aren't universally held. Those who are likely to be affected can be identified through genetic testing. They can then be moved off-world, so that any future children won't be affected by the process. The Alliance argues that this the least traumatic option.
Third, some people don't like being poked and prodded by the Alliance. They aren't interested in genetic testing. They aren't interested in relocation. And they don't give a damn about being 'good, compliant' citizens.
The moon is a harsh place to live. What difference does a body's sex make, as long as that body's still alive?
Once Jayne is fully dressed, Simon finishes with his own clothes. He notes the way that Jayne watches him, and how his expression – predatory, interested, planning – hasn't changed, even if the face wearing the expression isn't quite the same.
"Does Mal know?"
Jayne shrugs, and it's just as abrupt a movement as it ever was. "Nah. Never figured I'd be around long enough for it to come up."
Simon moves closer, and leans into Jayne. He takes a deep breath. "You don't really smell different." He breathes in again. "No. You do. It's just – the change is subtle."
Jayne snorts. "Subtle. Thought you said I'd never be that."
Simon tilts his head up, and smiles. "I guess I was wrong," he says, before stepping back. "So. How do you want to so this?"
"What difference does it make?"
Ultimately, Jayne's right. It probably doesn't make a difference at all. How the crew will react is rather predictable.
Wash will laugh, but not cruelly. Just out of surprise. Zoe might crack a smile. Mal will bitch about never being told anything, and how he doesn't like surprises. Kaylee will be delighted; Inara will probably be fascinated.
Book will smile benignly.
River may or may not notice. She may already know. In fact, this might explain some of the more cryptic remarks she's made lately.
Jayne is looking down at his – her – breasts. "These are gonna get in the way."
"I'm not sure I know what you mean."
Jayne reaches down and pulls a gun out of its holster, and aims it at the wall. "When I'm shootin'. See?"
It's true, Simon can see the way he has to compensate for his body's changes. Jayne's going to have to relearn how to aim. "Just think of the fun you'll have practicing, though. Also. You'll need some kind of ah – support. That will help things."
Jayne's expression turns dark. "I am gonna have to go shoppin'."
"Yeah. I guess."
"And while you're out, no one will recognize your face! This might help with us flying under the radar too – if anyone's looking for Mal and his hired male mercenary, this will be confusing. Probably long enough for you and Mal to deal with them." Simon knows his tone is overly enthusiastic, like he's trying to cajole, encourage. He can't quite help himself.
But Jayne brightens considerably. "Hey. Yer right. Think maybe I should ask for a raise, being all cunnin' like that?"
Simon laughs and walks to the ladder. "You could try. Come on. It's Kaylee's turn to make breakfast, and you know what that means."
"Food that has flavour." He grins, "She'll probably whip something special together, too, in honour of the new you."
"Shiny," Jayne says.