Title: Underneath Your Clothes
By: Caroline Crane
Fandom: CSI: Vegas
Pairing: Nick/Greg
Rating: NC17
Summary: Nick never really saw the appeal of cross-dressing. Until now.
Author's note: Personally, I don't have a guys in skirts kink. Probably because one of my best friends in high school was a cross-dresser, and I never had any sexual thoughts about him at all. But I know several of you do, and I, am a shameless attention whore, live to serve. I hope I did justice to the concept. And yes, there's a pop music theme. I haven't gotten much sleep this week. In case you're late to the party, what follows is a continuation of this.

He wasn't really expecting Greg to go through with it. He should have known better; Greg wasn't the type to turn down a dare, and it wasn't like he'd ever been shy. So it shouldn't have surprised him to open his door and find Greg leaning against the doorjamb, a trench coat hanging open over a Manson t-shirt and a little plaid skirt.

It wasn't a kilt. At least he didn't think it was; it was more like one of those Catholic school uniforms, and there was no way Nick was thinking about Greg in Catholic school. He wasn't sure he could think at all, because the sight of Greg standing there smirking at him sent all the blood in his body straight to his cock.

"So are you going to let me in or are we putting on a show for the neighbors?"

Nick blushed and tore his gaze away from Greg long enough to look around, making sure none of his neighbors were actually watching before he grabbed Greg by the front of his shirt and pulled him inside. He might have remembered to kick the door shut, but he couldn't be sure, because as soon as he got his hands on Greg all he could think about was finding out exactly what he was wearing under that skirt.

"Do I want to know why you own this?"

The question was out of his mouth before he could stop it; the truth was that he really didn't want to know, because even after all their time together there were still some things about Greg's past Nick didn't need to hear. If he knew Greg was being honest about everything it might be easier to take, but half the time he was almost sure Greg was making it up just to shock him.

He really didn't want to know where Greg had worn the skirt before – who he'd worn it for – let alone why he owned it in the first place. Didn't want to picture Greg in his skirt, someone else's hands traveling up his thighs. Someone else's fingers catching on the material – wool, he discovered when he slid his hands around Greg's waist, under his shirt to slide along the waistband of the skirt.

"Why wouldn't I?" Greg finally said, his breath hot against Nick's cheek. "You mean you've never tried on a skirt? Not even back in your homoerotic frat boy days?"

Nick rolled his eyes at that, hands dipping a little lower as Greg marked a trail of kisses along his jaw. "There wasn't a lot of recreational cross-dressing at A&M."

"Don't knock it 'til you try it," Greg answered, and Nick could feel Greg's grin against his neck. "This skirt got me a lot of phone numbers. Then again, maybe that was my legs."

And now he had to know, but he wasn't going to ask. He could tell Greg was waiting for him to lose his patience, to demand to hear all the details and Nick wasn't about to give him the satisfaction. Instead he turned until their mouths were pressed together, tongue pushing past Greg's teeth to kiss him hard.

A muffled 'mmm' was his only indication that Greg wasn't expecting the kiss, fingers gripping the front of Nick's shirt hard to pull him close. Nick's own hands slid down Greg's hips, the wool rough against his skin as he inched the skirt up. He could feel Greg's cock pressing hard against his thigh and he knew Greg wasn't wearing anything under the skirt, but his cock still twitched when he slid one hand across Greg's bare ass.

He'd never really gotten the appeal of cross-dressing, never really understood why a guy would want a guy who looked like a girl when he could just have a girl. But he definitely got the appeal of Greg, of his bare skin under Nick's hands and he had to admit that the thought of fucking Greg while he was still wearing the skirt was kind of hot.

Really hot, if he was being honest, because he'd thought about it more than once during their shift and he'd spent most of the night half-hard and glancing at his watch every five minutes. It hadn't helped that he was working with Greg for once, watching him move and listening to him talk about the evidence like he wasn't distracted at all. Like he had no idea what was going to happen as soon as their shift was over, and part of Nick had actually considered pushing him up against a wall and fucking him right in the lab.

"This part of the outfit?" he asked when he let Greg up for air, one hand still splayed possessively across Greg's ass and the other on his hip to push him backwards toward the bedroom.

Another smirk, and Nick swallowed a groan when Greg leaned in and dropped his voice to a whisper. "Well, I've got this pair of little white panties, but I figured you'd be in kind of a hurry."

And maybe he really did have a thing for women's clothing after all, because the thought of Greg in a pair of lacey white underwear sent a thrill straight down his spine. Greg in pretty much anything usually had that affect on him, but until now he never really thought it mattered what Greg was wearing as long as it didn't take more than thirty seconds to get it off him.

Greg's trench coat hit the floor first, followed quickly by their shoes and both their shirts. By the time they made it to the bed there was a trail of clothes stretching down the hall, and by the time Nick pushed Greg backwards onto the bed he was naked except for the skirt.

Part of Nick wanted to pull that off too. He didn't want to need it – didn't want Greg to know exactly how much it turned him on – but when Greg grinned and pulled Nick down on top of him he didn't protest. He didn't argue when Greg took his hand and slid it back under the skirt, fingers threaded together and circling his cock until Greg was moaning and arching up against him.

"You have no idea how many times I've thought about this."

The words were mumbled against his neck, Greg's voice so low that at first Nick thought he'd imagined it. Only Greg was still talking, voice breaking a little with each stroke of Nick's thumb over the tip of his cock, and every word sent a fresh shiver of want down Nick's spine. Words like want you to fuck me murmured against his skin, against his mouth when Nick pressed their lips together for another hard kiss.

One of Greg's legs was hooked around his thigh, pulling him impossibly closer and their hands were trapped between them, gripping Greg's cock and he could tell how close Greg was. Wasn't sure how long he was going to last either, so he pulled away to look down at Greg, taking in flushed cheeks and swollen lips before he pushed at Greg's hip.

"Turn over."

And just like that Greg was scrambling onto his knees, like he'd just been waiting for Nick to say the word. Like he really had thought about this a million times, pictured Nick behind him and the skirt bunched up around his waist while Nick pounded into him. Just the thought was enough to make Nick's cock twitch painfully, and it was all he could do to tear himself away from the sight of Greg long enough to find some lube.

He coated his fingers first, dropping the tube on the mattress and pushing the skirt up Greg's hips to push two fingers inside. Greg moaned at the slow press of Nick's fingers, pushing his knees a little further apart and dropping his head onto his arms. His back arched with each thrust of Nick's fingers, body flushed and shaking and Nick knew pretty soon he was going to start talking again.

Part of him wanted to skip the prep work and just slide inside Greg, but the rest of him wanted to hear the words. Wanted to hear Greg demanding, telling Nick what he wanted and pushing back hard against his fingers until Nick finally gave in. He wasn't sure how long Greg held out – a few minutes, probably, but it felt more like hours – before he was craning his neck to look back at Nick, grinding out a harsh fuck me through gritted teeth.

He moaned when Nick's fingers disappeared, legs trembling with the effort to hold himself up while Nick rolled a condom on and ran slick fingers over his cock. Before he pushed inside Greg he knew he wasn't going to last long, but when he finally slid into slick heat he had to bite his lip and squeeze his eyes shut to keep from coming. And even that didn't help all that much, because he could feel the roughness of wool under his fingers and picture Greg on his knees, the skirt bunched around his waist and the scars on his back standing out in stark relief against his flushed skin.

Greg was moaning, murmuring mostly incoherent words of encouragement, but they'd been doing this long enough for Nick to decipher what he was saying. He wanted more, harder and faster and before long Nick was pounding into him, each thrust a little more wild than the last. Greg pushed back to meet each one, angling his hips just so until it was all Nick could do to hold on.

Later he wouldn't be sure who came first. He thought it might have been Greg, balancing himself on one elbow to reach under his skirt and grip his own cock, tightening reflexively around Nick when his orgasm hit him. He was pretty sure Greg came first, but it was hard to say because as soon as Greg tensed Nick let go and came.

He held himself up long enough for his body to stop shaking before he pulled out, collapsing onto the mattress next to Greg and he knew he needed to clean up, but he was pretty sure he couldn't stand up. It was possible he'd never feel his legs again, but at the moment he didn't really care. He didn't care about much of anything except the way his heart was beating, pounding so hard he was sure Greg could hear it too.

Or he would be able to if he hadn't passed out, sprawled on his stomach with that damn skirt still hitched up around his waist. Nick wished he had a picture, or maybe even a video camera, and there was definitely something to be said for this whole cross-dressing thing after all. He laughed at that, breathless and surprised and he was still grinning when Greg stirred and looked up at him.

"Now that's the best hundred bucks I've ever spent on a Halloween costume," Greg said. He was still breathless, but he sat up anyway, unfastening the skirt and kicking it off before he stretched out next to Nick. "Although I think I'll skip the wool next time. Damn thing itches."

"Halloween costume?" Nick echoed, glancing at the skirt still sitting on the edge of the bed before he turned back to Greg.

"Yeah," Greg answered, and it amazed Nick how smug he managed to look when he was still flushed and panting. "Three years ago, Britney Spears. I'll wear the whole outfit next time if you want. Thigh-high stockings, white blouse, blonde wig...even the panties. If that's what you're into."

It wasn't what he was into. It wasn't, but he'd learned a long time ago that when it came to Greg, the usual rules didn't apply. "I could live without the blouse. And the wig."

He expected Greg to make fun of him, to laugh and remind Nick that he should try new things more often. But he didn't; instead he just grinned and closed his eyes, arching his back in a stretch that made Nick want to start all over again. "So you want me to wear the panties next time. No problem."