Thank you to everyone for reading and reviewing! It really helped me get of my ass and crank this one out (although this chapter came much easier for me than the last). This is probably going to be the last update for about a week, I'm taking a week off from work and visiting some friends out of state, but I'll do my best to work on the next chapter during my little vacation so it will be ready to post as soon as I come back! Hope this will tide you guys over until then!

"Sixth rule, no shirt, no shoes."

"So I need to tell you something. Two somethings actually." He breezes into the room as if he hadn't a care in the world, but his tone was serious and he had that hard look about him; the kind he had after dealing with a difficult patient, or when something important, something really important, didn't go his way. It probably says something about her that she's started to recognize these things about him, but then he's talking again, so she remains seated on the lower bunk of the bed, and shoves her charts away from her, giving Mark Sloan her undivided attention.

"I should probably warn you, you're not going to like either of them" he cautions, standing in front of her in the empty on-call room, hands tucked neatly, efficiently into the pockets of his lab coat. She wonders suddenly if this is how it must feel to be a patient when you know in your gut that whatever news you're about to receive is not the news you wanted to hear. It makes Lexie feel out of place and edgy, and she doesn't like it.

She shrugs her shoulders, unsure of what he expects from her. "So one something at a time, then?" she asks, pushing a piece of hair back behind her ear as a nervous distraction, and Mark's face hardens, as if he doesn't like what he's about to tell her.

"Yeah" he sighs. He crosses his arms, folding them across his chest in what would have been a casual gesture in any other situation. "I made a promise to Derek, a while ago actually." She fails to see where she fits into this until, "About staying away from you."

He watches her carefully for her reaction, but finds nothing but a mild confusion. She blinks once, twice, and Mark can all but see the gears turning in her head as she tries to work this out. "I'm sorry, but I don't think I know what that means" she confesses, bringing her knees up to her chest so she can rest her arms on them. "Dr. Shepard made you promise not to talk to me?"

"It's not the talking that he's worried about." He looks her up and down quickly before speaking again (and he probably doesn't even notice he's doing it, she thinks, but it makes her flush a little anyway, his gaze raking over her). "It's what he thinks the talking will lead to."

Lexie could play coy or dumb, but she is neither of those things, and Mark doesn't expect her to be. He didn't, however, expect her to be so blunt either. "So Dr. Shepard doesn't want you to sleep with me?"

Mark takes a deep breath, settling himself on the nearest bed, facing her. "Yeah, he doesn't want me sleeping with you." They're both aware of how ridiculous this sounds; this is the stuff that daytime soap operas are made of, and while there is always a certain level of drama at any given day of the week floating around Seattle Grace, this somehow seems out of place. Mark doesn't seem as if he has anything else to add, so Lexie fills the silence.

"Dr. Sloan?"

He looks up at his name, a wry smile on his face that she still uses his surname. "Yes, Little Grey?"

She looks him square in the eye, almost apologetic, but some little detail has been nagging her since his confession and now seemed as good a time as any to clear it up. "Sorry, but, since when does Dr. Shepard get to decide who I get to…um, sleep with?" She stumbles a little over that last part, in true Lexie fashion, and Mark feels a surge of affection for her that surprises him. "Why would he care about…"

He rolls his eyes. "He doesn't. Meredith does, apparently. Derek is just a little wooden boy who happens to be dating your sister and she's the one pulling his strings."

Lexie is clearly confused. "I don't think I understand any of this. When did Meredith start acknowledging me, even if it is in the most convoluted manner I've ever heard of?"

"All I know is that Derek is the one who made me promise, and I can't break another promise to him." He shakes his head, almost reassuring himself more than he is her. "It's not really important to him except that he wants to make Meredith happy. And don't ask me how that works" he adds, seeing she had been about to interrupt, "All I know is I'm supposed to stay away from you and Derek found out that I didn't. Which is not… good."

Lexie just looks indignant, now, and her brow furrows in concentration, still trying to figure out the finer points of this arrangement. "So my sister told Dr. Shepard to tell you, to make you, stay away from me? Because you've pretty much done the exact opposite… in the, uh, basement" (her cheeks flushed a brighter red this time, and he wonders in silent amusement how long it will take for the color to go away) "And yelling at me after…"

"Crazy Sadie let you cut out her appendix?" he offered.

She lets one shoulder rise and fall in a half-hearted shrug. "Yeah. So, I guess my point is, why are you telling me this now?"

"There's the second thing" he reminded her, unsure of how to phrase it. "You needed to know the Derek thing first."

"Fine" she huffed, pushing her hair back away from her face. "What's the second thing? Please tell me I'll understand it better, at least."

"I'm not sure, and I don't know if you'll like it," he admitted, "but I'm used to doing what I want so I'm just going to say this anyway." He rests his hands on his knees to balance him, and takes a deep breath. "Little Grey …Lexie, I can't be your friend anymore."

The room is eerily silent, his words hanging in the air, but it seems like his words finally prompted her into action, the confession about Mark's promise not enough until now:

"What?" Lexie looks at him equal parts disbelieving and exasperated. "Is this because of the whole Derek thing, because that's just not fair. I know that he's your best friend and you made some stupid promise to him that he had no right asking for in the first place, but still…"

Mark gets up, moves to stand in front of her. "No, Lexie, listen – " but she continues on as if he hadn't interrupted. Her hands are gesturing furiously, though, and it's hard to get a word in edgewise (there's a part of Mark, anyway, that thinks maybe he'd like to hear the rest of this, because no one has ever really gotten this worked up on his behalf before. He sort of likes the feeling.)

"And really, I can't speak for how close your relationship with him is, but he doesn't get a say in what I do. Even if Meredith is sleeping with him or living with him, or whatever. Since when does she get to decide that she knows me well enough to say who and who I'm not allowed to…associate with?" Her tone is full of righteous indignation, and if what Mark had to say wasn't so important, he would have been perfectly content in letting Lexie continue. However, he knew, this was not the time, so when Lexie paused momentarily to take a calming breath, Mark took his opportunity to interject.

He kneels in front of her, hands resting solidly on her thighs. The contact makes her breath catch, and her head jerks up to meet his gaze. "That's not it at all. This has nothing to do with that."

"It doesn't?" and the questioning way she cocks her head, brow furrowed, makes him lean in to her, completely and unmistakably invading her space (and he wonders idly if she knows what she does to him with her lips formed in a subtle pout like that).

Mark shakes his head slowly, hands creeping up over her thighs until his fingers brush against the warm skin under the back of her scrub pants. He watches as she catches her lower lip between her teeth, eyes slipping closed for only a fraction of a second from his touch. "This is all me."

Hands at her sides she's clutching the bed sheets, twisting them around her fingers to keep from touching him. "That sounds good. That's a good thing, right?" She hadn't meant for her voice to come out so throaty, but Lexie found she was quickly losing any semblance of control over even her basic functions; her heart was hammering out of her chest, breathing becoming more and more erratic as Mark's cool fingers stroked her heated skin.

"It could be a very good thing" he agreed, moving closer still until he was nestled between her legs, her knees pressing into his sides. When her hands moved off the bed to clutch at his arms, pulling him by the sleeves of his scrubs nearer to her still, letting out a breathy kind of whimper, even the mere idea of restraint flew out the window. Mark darted forward, claiming her lips in a bruising kiss. Whatever her next words would have been were swallowed with his mouth on hers, and she moaned greedily, fingers grasping blindly at the back of his neck, keeping him pressed to her.

Mark pulled away first, pleased with the flush covering Lexie's cheeks. He kisses her again softly, only just touching his lips to hers, bringing his hands up to cup her face. His thumbs trail softly over her cheeks. Lexie leans into his touch, eyes fluttering shut as she rests her forehead on his. "So you still don't want to be my friend?" she asks, slightly breathless, and Mark can't help but laugh.

"I can't be your friend, Lexie, because I don't want to be just your friend." His fingers bury themselves in her hair, and when she nods, eyes still closed blissfully, he can feel her movement. Mark continues, far from hesitant now, although he wonders if his voice is really as loud as it sounds in the empty room. "Friends don't do to each other the kinds of things I want to do to you."

"Oh" she exhales in sudden understanding. She looks at him then, smoldering eyes from under dark lashes, and her fingertips trace the outline of his lips. Then she says what is possibly the single most beautiful sentence anyone had ever spoke to him: "Mark?" (His name was like a question, unsure and shy because she'd never called him anything but Dr. Sloan before) "I don't think I want to be your friend either." They both knew what she meant.

His mouth was slanted hungrily over hers the moment she got the words out, hot and demanding and Lexie responded eagerly when his tongue slid over her lower lip. Her hands were frantic now, wanting to touch everywhere at once; they slid over the back of his head, brushing agreeably against his soft, short hair, before tracing the sides of his neck. She felt him shift their positions, pushing her gently back onto the bed while he rested his weight over her, propping himself up with this arms. The mattress groaned from the sudden weight, and the sound made them pull apart, both breathing heavily.

Lexie wriggled underneath him, settling down onto the bed, and the movement sent a wave of desire coursing through Mark. He closed his eyes as her hips rose to press to his, her back forming an arch against the bed, fighting back a groan of his own. Her hands were clasped behind his neck, pulling him towards her, and although Mark had never imagined Lexie to be so brazen, he found he quite enjoyed this side of her.

"Please, Mark?" She asked between pressing soft kisses against his jaw line, his lips, his eyelids. "Technically, you're not breaking your promise if I don't stay away from you." (And leave it to Lexie Grey to be concentrating on something as insignificant as the specifics of a contract when there is the immediate promise of more pleasurable activities present.) Her fingers were stroking down his back now, raking her nails over the skin just above the neck of his scrub top, and Mark couldn't help but return the favor, brushing his fingers up her sides. He was trying, for Derek who was his best friend and deserved his loyalty even if the promise he made was ridiculous, to keep himself under control, but Lexie was having none of it. She shivered under his touch, the cold air of the room making goose bumps appear wherever his hands had been. His fingers stilled, however, at the bottom of her scrub shirt, one movement away from lifting it up.

His eyes locked with hers, questioning (and for what might have been the first time he could remember, hesitating). "Please?" she asked again, tilting her head up and capturing his lips in another intense kiss that left them both out of breath at the end. "I want you to."

In that moment, with Lexie's eyes glassy and focused only on him, her body fitted to every inch of his, those four words were more binding than the repeated promises he'd made to Derek. And Mark realized later, when she gasped his name, breathless and panting as he sank into her, that whatever happened when they left this room would be totally and completely worth it.