John's afternoon at the surgery had been particularly brutal, leaving him exhausted. A nap sounded good - possibly just a quick snack and then an hour or two to recover before facing whatever strange experiments his flatmate had decided to conduct in the kitchen sink while he was gone. Maybe he'd even skip the snack, go straight to bed, ignore the experiment. He wasn't that hungry anyway.

John climbed the stairs, opened the door, and froze. His mind seemed to split into two parts. The first was mesmerized by the woman pacing the living room in front of him: impossibly sexy legs going on for miles between her short black skirt and her tall black heels (the source of the clicking as she paced, John surmised), just enough volume evident beneath her tight midriff-baring sweater to keep her frame proportional, and damn, that impressive glimpse of taut stomach in between the sweater and the skirt . . .

She was tall, possibly even taller than Sherlock. A model, perhaps? The unusually short black hair, slicked back under a stretchy headband and artfully spiked, suggested model or actress were both possibilities. The breezy silk scarf tied around her neck looked hideously expensive. John knew next to nothing about women's fashion, but the entire outfit looked good - very good - on her. Good enough that she probably knew what she was doing, fashion-wise. The makeup was spot-on, accentuating her pale skin and dark hair with touches of bright red lipstick and something shimmery around her eyes . . . those eyes . . .

"Sherlock?"

Sherlock propped a hip (slightly more rounded than his own - padded?) against the arm of the sofa and grinned. "What gave me away?"

"Fuck, Sherlock! Why are you dressed like a model? A female model? In our living room?"

"Case." He frowned, although in his current disguise, it came out looking more like a pout. "You weren't sure when you came in, though, so it wasn't immediately obvious?"

"Not many women over six feet tall." John paused, but Sherlock was really and truly listening to him for once, so he went ahead and ran through his deductions, such as they were. "Tall, short hair, good makeup, expensive clothes, all say model or actress, but I'm guessing you were going for model. Scarf was to cover your Adam's apple, I assume? Good color for you, by the way, although I'm a bit afraid to ask how you know so much about making yourself look feminine. Your eyes were what gave you away, and I doubt someone who didn't know you well would pick up on that."

"Well done." Sherlock's frown melted away, replaced by a look John usually referred to as "charming Sherlock." He'd seen it several times before, usually used to wring information out of women (and occasionally men) while they were on a case, but this was the first time the full force of Sherlock's charm was turned on him. It was . . . disconcerting. And sexy as hell, even knowing the gorgeous woman eyeing him was actually his flatmate.

"What's going on?" John repeated, for lack of anything better to say. With anyone else he'd be looking for the hidden camera, waiting for the other shoe to drop, but this was Sherlock.

Who merely tilted his head and regarded John lazily. "We've got a date tonight. Extremely exclusive venue. I laid out your outfit on your bed upstairs - you should have just enough time to change before we go."

John blinked. "A date. With you."

Sherlock nodded.

"And you're in drag."

"Disguise." Sherlock's shoulder lifted in a quintessentially feminine shrug. "The invitation wasn't intended for a male couple. Plus I know you consider yourself straight, so you might have balked at going out in public with me in a romantic sense if I were dressed like I normally do."

John's mouth opened to argue - I am straight, you nitwit, I have no interest in a date with you, you look fucking gorgeous right now and I had absolutely no idea - but the last bit cancelled out the first bit and he ended up not saying anything at all. "Give me a minute," he finally said, and stomped up to his room.

There on the bed was a new suit, neatly laid out, dress shirt and jacket and trousers, down to the underpants and socks and a shiny new pair of shoes. All in exactly his size, even the shoes which were normally impossible to shop for because John's toes were wider than his heels and he usually had to try on twenty or thirty pairs before he found one that actually fit. There was something scary about Sherlock having delved through his dresser and closet and sized his clothing like that. Sherlock having selected every stitch he would wear on their "date." John tried not to think about it as he shucked his jumper and changed.

Sherlock was pacing again when John came back downstairs. He looked absolutely at home in those frighteningly high heels - the pacing was all Sherlock, but the stride and the sway of the hips were undoubtedly feminine and were doing strange things to John's brain. And his groin.

What the fuck is wrong with you? He's your flatmate, that's all. He does weird stuff like this all the time. John tried to convince himself this was just another Sherlock thing, just one more way Sherlock was completely impervious to normal human things like boundaries and personal space and not bloody messing with his flatmate's head, but then Sherlock smiled and the bright red lipstick emphasized the curve of his lips and John was right back where he started, scrabbling to find some sense of normal in the situation.

"That looks good on you," Sherlock purred. He actually purred, a sexy rumble which did absolutely nothing to help John restore equilibrium. "We should get going."

John didn't move. "At least tell me what the hell we're doing tonight. How it relates to a case." A thought suddenly occurred to him. "Dear God - please tell me this is for a case, right? You don't just dress up like this for kicks?"

A flash of confusion flickered across Sherlock's face. A nice, normal expression, one John had seen many times before, which strangely went a long way toward calming his nerves.

"It's just, you seem very natural in those shoes," John felt compelled to add. "And all the rest of it."

"Well I did have all day while you were gone. Took forever to shave everything. And it's not like I've never done this before."

"For a case?"

"A few weeks, yes. Tonight's invitation was from an artist who knew me as Shirla, when I was, yes, a model. Magazines. I think I actually ended up in one, even after the photographer got arrested."

"For what?" John felt obliged to ask.

"Not all of his models were of age. Or clothed."

"Ah."

Sherlock waved the memory of the old case away with a dainty flick of his wrist. "Not relevant to tonight."

"But there is a case?"

"Probably. Blackmail, clearly, but not clear who. Hence our date."

John still made no move toward the door. "Going to tell me any more about it?"

"Not yet. I don't want to bias your observations." Sherlock stalked toward him, hips swaying, and John had to fight not to swallow hard while Sherlock could see. "Call me Shirla tonight, should be close enough to 'Sherlock' to not be too confusing. And try to look besotted."

John blinked.

Sherlock drew up just short of John and frowned. "No, not like that. Like you're not entirely sure how you ended up watching an erotic performance artist with me at your side and you can't believe your luck. Half dazed and half desperate."

"I . . . erotic performance ar-"

And then Sherlock dipped his head and kissed him, and John's brain shorted out entirely. Sherlock's lips were warm and gentle and still somehow demanding, until John finally gave in and opened his mouth and kissed back and Sherlock's tongue swept in and cleared out the remains of his sanity. When John finally opened his eyes and drew back, he discovered his hands were gripping Sherlock's shoulderblades through the sweater and Sherlock's fingers were gently stroking his jawline.

"Fuck."

Sherlock grinned. "Not yet."