Disclaimer: If Grey's Anatomy were mine, there'd be a lot more sex and very little medicine.

A/N: So, I really should have been writing lizadizzle's Grey's/CSI: Miami, Callie/Natalia fic, but this came out instead. *looks sheepish* I'm also choosing to ignore the new 5x10 "All By Myself" promo (even though I squeed like the el retardo fangirl that I am when I saw it) simply because I started writing this before it aired, and it really fraks up the entire story if I had taken it into account.

Mark had been avoiding her for two weeks now. Two painfully long and frustrating weeks.

And all of it was Derek's fault.

If he would've just kept his big, fat, McStupid mouth shut, none of this would have happened.

He wouldn't have felt like the world's biggest asshole the first time he completely shut Lexie down. Or had to slink around the hospital like a common criminal, hiding in storage closets and on-call rooms every time he couldn't simply run away from her.

It was cowardly, but necessary if he was going to keep his word.

Mark hated it.

And it only got worse from there.

After nearly a week of hearing his lame ass excuses, which frankly even he stopped believing somewhere around the third day, she'd made it her mission to be assigned to his service whenever he was in the hospital.

Not long after that, wild stories about her had started rapidly floating around the building. Some were hilarious and others were awe inspiring at her stupidity, but all of them depicted over exaggerated tales of her angering Yang to the point of banishing her to plastics, if for no other reason than to just get her out of her sight.

Everyone, from inters to residents and attendings, thought she was absolutely crazy for taunting the beast. Including him.

But no one else knew why she was doing it.

That was by far the biggest question on everyone's minds.

Some thought that she was just another Grey acting out, but everyone had known that Mark was avoiding her. So logically a majority of the staff, mostly of the female persuasion, had come to the conclusion that it was his fault; he was a manwhore who'd been looking to put another notch on his bedpost before moving on. As simple as that.

Apparently, their most popular theory had been that the intern hadn't taken too kindly to his ways and decided to get her revenge via stalking and annoying until he broke.

Nobody knew that he didn't want to be that guy anymore, and hadn't been since Bailey had saved his ass from the nurses "United Against Mark Sloan" club.

It wasn't one hundred percent his fault though.

Sometimes he wished she didn't have that damn annoying Grey stubbornness burned into her genes. Normally, he found it endearing, before he'd seen her in this new light, that she stuck to her guns when it counted. But it would've saved them both a lot of pain and frustration in the long run if she'd just kept to herself and left it alone.

Left him alone.

He'd felt horrible treating her that way. Trapped. Backed into a corner like a scared animal, forced into lashing out at any opportunity just to keep her away. A last resort.

His heart broke with each insult. Hating how easily it came to him, how second nature it felt. He'd seen her happy and sad, ecstatic and upset. But he'd never get the look of confusion, hurt, and anger that always seemed to adorn her face whenever she was around him these days, out of his head. Constantly forcing his guilt to the surface. Especially after all she'd done to get there. To get to him.

He kept having to tell himself that it was for her own good.

She deserved better.

That thought alone, that he actually cared whether or not he was good enough for her, scared him more than any of the consequences he'd been threatened with if little (big) Sloan should ever happen to enter Little Grey. Nothing. Not even the graphically painted image of Derek wielding a ten blade, using no anesthesia while he got his most treasured bits surgically removed.

As much as he hated to admit it, he'd changed.

The "old" Mark would have laughed at such a warning and slept with Lexie anyways, without a second thought or regret.

But, the "new" Mark?

Well, he was failing to see how this was better than hot sex. Any sex, really. But he figured that the old adage, "Good things come to those who wait," didn't just appear out of nowhere. There had to be some truth to it, right?

So, the "new" Mark? He didn't want just one night of hot, anonymous sex. He wanted more than that.

He wanted Lexie.

And after two weeks of torturing her (himself) he'd finally felt his resolve starting to slip.

He wouldn't be able to control himself much longer.

Which is the main reason he'd almost run for cover earlier that night, exactly fourteen days later, when he'd spotted her at the nurses station down the hall, hunched over, writing lazily in a huge binder.

His shift had just ended and he'd been looking forward to finally going home for the evening; a chance to relax and recuperate mentally. But for some reason, with his jacket slung over his shoulder, curiosity had gotten the better of him and he'd scanned the small crowd looking for Lexie as he waited for the next lift to arrive.

He should have known better. Shouldn't have tempted the fates.

Staring at the wall, like he'd planned on doing, would have been so much safer.

He'd been so close.

Seconds later, the elevator had dinged its arrival and he'd walked inside, leaning wearily against the railing in the back. Still watching her for a last few precious seconds.

That's when she'd looked up, her gaze drawn to his.

His throat had tightened, breathing forgotten, mortified that he'd been caught and guilty for breaking his promise to begin with.

She'd looked exhausted, though. Dark rings had grown under her eyes, normally well kept hair was frizzy and disheveled. And, even from where he was standing, he could tell that she was only a few seconds away from crying. Her bottom lip quivered between her teeth, brow furrowed slightly, tears just about ready to wet her lashes.

It tore him up that he'd done that to her.

He'd completely crushed the poor girl and she'd never even had a clue why.

Mark had never hated Derek more.

His eyes had softened and broad shoulders sagging in defeat. Finally giving up the charade. Regret painted brightly across his face.

With their eyes still locked, doors sliding quickly shut, he chanced mouthing one word just as he disappeared.

"Sorry."

He'd regretted it immediately. Spent the entire drive home, and most of dinner, agonizing over whether he'd made the right decision by apologizing to her. Wondering if she'd even gotten the silent message. Hating himself for fretting over it in the first place.

It'd been a spur of the moment decision. Not even aware that his lips had been moving until after he'd already started his decent to the lobby.

He felt like a lovesick idiot.

Mark was not a teenage boy, he was a grown man. He didn't moon over pretty girls or care about their feelings. And he certainly didn't sit alone in a dark room wallowing over a non-relationship.

It was pathetic.

Absolutely downright, infatuated, thinking with his heart, Disney movie, pathetic.

The irony didn't escape him.

So hours later, just after finally settling into a fitful slumber, when he was startled awake by a timid knock on his door he couldn't say that he was surprised.

There's only one person he knew who'd knock like that, like a girl scout who'd lost his cookies and couldn't give him a refund. Only one person brave (stupid) enough to even risk visiting him at four o'clock in the morning on his day off.

It had to be Lexie.

How had she found him?

Mark groaned and rolled over, ignoring her for the moment, wishing halfheartedly that she'd just go away. Knowing that if he let her in, if he let her truly see him, nothing would ever be the same.

She knocked again, this time a bit more forcefully, and he knew if he didn't let her in she'd probably make a spectacle of herself and by association, him.

Sighing heavily, he stumbled out of bed, flicking one of the lamps on as he passed it and slowly made his way to the door.

Was he really going to do this?

None of it seemed to matter anymore. His willpower had vanished, completely broken and gone, along with the ability to continue pushing her away. Even if he wanted to stop himself, he didn't think that he actually had a choice at this point.

Still donned in his boxers, bare chest, hair rumpled, one sock missing beneath the covers, he grasped the door handle and turned, not quite ready for the little ball of fury that he found on the other side.

Little Grey was pissed.

She pushed quickly past him, glare in place, a blur of angry woman. Full of energy as she began pacing back and forth.

"Why won't you talk to me?" she blurted out accusingly, "Why do you avoid me at any cost? Did I do something wrong? Did I say something to upset you? Because honestly, you've been a complete ass over the last few weeks and I didn't do anything to deserve it, dammit! What the hell is gong on with you to make you treat me like this? I mean, I know I'm just a lowly intern, but I thought I knew you a little better than that. Just- tell me why. I at least deserve that much if this is going to continue."

All Mark could do was let out a deep breath, hand rubbing over his face as he tried to process.

She was right. She deserved to know what was going on, even if she didn't return his feelings in the end.

So he met her questioning eyes, taking a tentative step toward her. "Do you really want to know the truth?"

Lexie's head cocked to the side. "Of course I want to know! Why do you think I asked if I didn't want to know the truth, Dr. Sloan?"

He nodded, relieved and nervous at the same time, taking another step forward, and then a few more. Watching as her body tensed slightly, feet shuffling backwards the closer that he got. Not stopping until he had her pinned against the wall, fingers tangled in her hair, their mouths inches apart.

"Are you absolutely sure you still wanna know?"

Her eyes widened. Hands hovering mid-air clearly not quite sure what to do with them. Remaining quiet, studying him with a confused, yet adorable, face.

She may not have expected this when she showed up at The Archfield looking for him, but she wasn't pushing him away or yelling at him anymore, so that was a good sign.

Taking her silence as a yes, he leaned in slowly, giving her every opportunity to protest. They were so close. The smell of her shampoo swirled around him, dizzy with anticipation. Lips just about to touch.

"What are you doing?" She whispered with a hint of panic in her voice, pulling back slightly.

"Shut up."

Before she could say another word his lips covered hers, pulling her into a fierce kiss.

It was rough and sweet. Bodies pressed tightly together. Nipping her bottom lip until she gasped, sweeping his tongue inside. Tasting her, exploring, finally allowing himself to touch her.

His entire world had come down to this- her. She was all he could focus on.

Mark groaned. Slender arms wrapping around his neck, fingers curling into his hair. His hand slid down her side, caressing the sliver of soft skin bared between the hem of her shirt and waist of her jeans.

She arched into him- soft curves gliding along his bare chest- making him shiver and grind his hips into hers.

He wanted her so badly.

To feel her skin against his. Let himself go. Lose himself in her.

But, finally feeling her length along his body, hearing the way that she whimpered every time their tongues collided, feeling her writhe against him, it was too much. All of his sense were overloading, brain and common sense melting away. That frightened him.

Enough for him to slow the kiss down. Gentle passes. Lingering. Lips finally breaking apart, foreheads resting together. Breath puffing across his chin as he waited for their pulse rate to slow back to normal.

He was basking. Though he'd never admit it. Only girls did that.

He'd just made out with his best friend's, girlfriend's, little sister and he'd stopped it before things had gone too far. So, maybe he was a girl.

But- oh no.

His stomach clenched, churning in mild terror.

He just made out with his best friend's, girlfriend's, little sister!

Shit .

He was so dead.

Mark groaned, "Derek is going to kill me."

End.