This is not my fault. It's for Ronin Blackwing, who suggested something just a little different but this is what came to me and wouldn't go away no matter how hard I tried. Hope you like it anyway, Ronin! For everyone else, this is all Ronin's fault. Address complaints to them.

Chapter 1: Going once

She'd been furious when the dress turned up. She doesn't need help (even if she'd had nothing to wear – how is she saying that: she always has the right thing to wear) dressing. Fury had lasted right till the moment she looked at it. Perfect colour – she absolutely adores that shade of red. Blood red may not be the most appropriate shade given her profession – blood on the floor means something's badly wrong, though as long as it's not hers it's generally okay - but the colour suits her. Perfect size – if she thought about it, that would be really, really worrying. He's never put so much as a finger on her, so how on earth can he judge her size that accurately? Observation clearly means more than she thought. It's not just her work attributes he's been observing. Not that he'd be shy of continuing his observations by putting a – or all ten – fingers on her. That's been very clear from moment one. Do not think about that, Kate. Now is not the time. She's working. Perfect style. She may not be well-endowed, but she's got enough there to fill some very pretty lingerie.

Not that she can wear it, under this dress. Not only is it strapless, and plunging to boot, (even the boys looked at her with admiration: they've never looked at her like that before and if they value their lives they never will again) but the designer left out any concept of a back panel in favour of some very, very sexy lacing. It's so low in back that she couldn't even wear a bra designed for backless dresses. Just putting it on made her feel naughty in ways that puddle down low in her body. She thinks she's doing a good job of hiding those feelings. She is, after all, here to work. Castle, on the other hand, is not hiding his feelings at all. It's very unreasonable that he's tall enough to look downward like that. She's certain that he's enjoying the view. He's certainly spending enough time staring at it. Much more staring and the dress will incinerate. That'd be embarrassing. Even when she'd modelled lingerie all those years ago she'd not needed to go topless. If they weren't at work, now… well, it wouldn't necessarily be a problem. Admiration is always nice. What? Left field calling. That was a wholly inappropriate thought. Of course it would be a problem.

It would be a lot easier to work if Castle didn't look so amazingly good (you mean sexy, Kate) in a tux. All men look better in tuxes. But it's entirely unfair for one particular man to look so… well, edible. Mmmmm. She could eat him right up. Then he could eat her right up – stop. Now. That thought is not conducive to catching a killer.

A line up with this lot would blow the precinct cameras, with all the glitter from all the bling. Well. It's not bling, because it's real, and expensive. When it's this much of New York's high society having an event their adornments don't get described as bling. Even if it is. She's perfectly sure that no-one here talks street slang. Not that she can talk about bling, or lack thereof. The dress sparkles, the necklace Martha lent her sparkles, and she's fairly sure that her eyes are sparkling. Nothing to do with her response to Castle's eyes. Which are also sparkling. Quite ridiculously attractively.

She glares around the room, at a reduced wattage in order not to frighten the society belles and beaux. She'd rather be interrogating the lot of them, on home ground. Especially, she'd like to interrogate the woman who's picked off Castle at the bar and appears to be interrogating him. This is not a date, but it's still very rude to monopolise someone else's escort. From the hunted look on his face, he needs rescued. Well, he'll need to rescue himself, because Beckett needs all her rescuing abilities to evade the woman – or barracuda, from the expensively dentally enhanced toothy smile – who's just swum up to her in the hope of finding out how she, Beckett, managed to get her – the implication is unworthy – hands on Castle. Well, she hasn't. Got her hands on him, that is. Nor he on her. Though she's absolutely sure he'd be very enthusiastic if she suggested it. And her hands are thoroughly worthy. Which thought is not helping her find a lead.

Nor is this. Castle clearly has rather more talents than tossing out unlikely theories and being irritating. (though she secretly enjoys the effort he puts into irritating her. It amuses her, and she knows that he knows that her snark in return is because he's become part of the team. Not that she's telling him that.) The man can dance. Someone that big usually can't. Or they're too…forceful. It's not a sixties hop. She doesn't need flung around. In this dress, it might cause a wardrobe malfunction. She couldn't find her modelling tape. She used the last of her duct tape to fix a wire under a shelf.

She has to remember that she's working. Because otherwise she might just quite unreasonably and stupidly succumb to the temptation to move a little closer in – he's not pulling her in, but it's perfectly obvious that if she evinced the slightest desire to be closer he'd oblige – lay her head on his shoulder, maybe undulate a very little (more is definitely tacky, in public – what?) and let the warmth of that large hand keep her there against a rather impressive body. Sadly, she can't. She's working, dammit! It's the first time ever she wishes she wasn't. That feels very nice. Very nice indeed. Why's she not done this before? What the hell is she thinking? She needs to get her mind (and body) under control, stat.

Oh. Yeah. Because this is his milieu not hers. Rich playboys, bored rich women, paid for escorts of both sexes. She doesn't belong here. Paparazzi and diamonds aren't her scene. Though from the look Castle's still giving her, it's not his either. She's fairly certain (through his lack of control of his physical – er - reactions) that his scene currently encompasses her, the dress, a floor covered in said dress, and a bed. Mmmm. She could cope with that. What? That came out of left field too. She couldn't. Definitely not. And now his fingers are misbehaving very slightly. Nothing indiscreet. Just as well. She doesn't need to be on page six. PR is not an advantage, in her line of work. She'll get quite enough grief from the boys tomorrow without adding that. But his fingertips are moving. Gently. Extraordinary, how much heat is coming from his fingertips. It's all concentrating down low. He shouldn't be doing that. She shouldn't be enjoying it.

Well, she was enjoying it. Being abandoned on the dance floor really does not do it for her. Very bad manners. She'd never previously thought he was bad-mannered. Annoying, flirtatious, and inappropriately mannered, yes. Bad-mannered, no. He's generally very well-mannered. Too much so, when it comes to exploring doors with bad guys behind them. He shouldn't be trying to open them for her. Spoils the surprise.

Oh. Ah. He's found her a lead. That does it for her. Well. Helps. Oh yes. Oh no. Another left field thought. But she does like success. Oh. It's not a lead. It's a confusion – that's not English. She speaks better English than that. Who is this old man, anyway? Apart from a very charming flirt. Even better than Castle, in fact. She should tell him that. Castle, that is. He's so funny when he's spluttering in outrage. She's just about to do so when the lights go up on stage and – oh my God, it's Martha, and this old man is snickering, and Castle looks utterly, utterly dumbfounded – he must be, he can't even speak, which is unheard of – and she just knew she liked this man whoever he actually is: he's got charm, personality, wit – and he's reduced Castle to speechlessness. Maybe he - this old man - would like to come for a drink sometime. He's really interesting.

Her respect for Martha's taken a high jump – not to mention a pole vault – upwards, too. No wonder Castle had been so flustered when she'd told Martha where they were going. She and this old man – Powell, that's it – must have planned this in short order. Still, surely it can't be as embarrassing as Castle's current level of cringe would indicate. Unless there's some history she doesn't – ah. Hold on a moment. Something's nagging at her mind. Powell. Powell. Why does that name ring a bell in the Castle context. Powell … jewels…confusion…accusations – oh my lord. This is the Powell to whom Castle dedicated a book. He would indeed be really interesting to talk to over a drink. Of the precinct coffee, in Interrogation. If only she had some proof. Or evidence. Or even half a reason to suspect him. His eyes are twinkling irresistibly mischievously at her. She's sure this Powell knows exactly what she's thinking. She twinkles back, only marginally diluted by a soupcon of glare, and turns her attention to the stage. Martha's stage presence is phenomenal. She sees where Castle gets his personality traits from. Though in his case it's at least as much that he's far too sexy for his own good. Or hers. Stop that. She's still working. Dammit. No. Not dammit. Not at all. Get the damn fielder out of left field. She doesn't have time for this.

Charity auction time. Let's show everyone how rich we are. Or in her case, aren't. She won't be bidding. She'd need to win the lottery. Twice. Given her luck, several million times. She's never so much as won a packet of sweets in the lucky dip. Everyone wins on the lucky dip. Except her. She got the plastic ruler. Madison got the box of chocolates. And wouldn't share, either. Not that Beckett's bitter. What's today's star prize? Week in the Hamptons? Month on Barbados? First class flights to Hawaii? How about something useful? A confession to murder? She'd take that one. Maybe Castle would subsidise her bids for that one. She should ask him. She's just about to share the joke when Powell says –

"Payback." Castle looks first adorably (what? Not adorable. Really not.) bemused and then horrified – and then his mother opens up.

"Thank you for that warm welcome. The first item on our list is a signed first edition of Storm Season, written by, well, by my son. There he is. Wave, darling, so everyone one can see you. Oh, isn't he handsome?" Castle is, well, gibbering. It's hysterically funny. He's embarrassed. So he should be. How come his mother needs to get him dates still? Beckett thought he was quite capable of doing it himself. Mind you, if he's been as successful with others as with her maybe he does. Maybe, given what Castle's said about her, his mother's hoping for a double date. She'll get a rich silver surfer and Castle will get a pretty younger woman. Hmm. That is an unpleasantly unwelcome unpleasant thought. Surely she's not bothered by Castle being auctioned? Oh. She is. Well, she shouldn't be. Really. She has no right to be bothered. So she can't be. There. Sorted.

"My still single son, ladies. So, as a special bonus, the winning bidder will also receive an enchanting evening in his company. Alright, ladies, that's the best I can do. The rest is up to you. Do we have an opening bid?"

Bidding's quick, and high. Castle's desperately trying to hide. When he's not cowering, he's pleading with Beckett to bid on him. When a rather handsome man bids, the pleas take on an air of terror. When it's a diamond encrusted senior (Beckett's sure that she's got diamonds soldered into the wrinkles in her forehead to replace her tiara) his pleas reach a falsetto squeak.

"Look, I have money," he whimpers. Whimpers. It's like listening to a smacked puppy. "Anything you pay, I'll pay you back."

Beckett can't stop sniggering. But then he turns enormous, pathetic, desperate blue eyes on to her. That wouldn't work. What does work is the unseen hand sliding over the bare skin of her back and down to her ass. She conceals her wriggle by main force. He must be desperate. Trying to suborn her with sex? Clearly he's willing to risk losing a hand to get her to bid. Just maybe this could have some serious advantages.

"Anything? Well now, Castle. Anything, hmmm?" She smirks. "Deal. I'll bid whatever it takes to win you. Then we'll talk about what the payback might be. Of course you'll cover the money, won't you? The payback's on top of that." He nods, frantically.

"Just get on with it, Beckett. Please? Before one of these senior sharks takes a bite out of me. Have you seen their smiles? I feel like I'm going to be dinner not taking someone out for dinner. No limit. Whatever you need to spend, I'll pay."

Beckett raises her hand. Martha clocks it, and ups the bid to $5,000. The diamond-doused senior doesn't like it. Another row of dentures appears on her face. $6,000. Beckett bids $7,500. Senior pauses, grimaces, eyes Castle up and down, stopping just south of his cummerbund. $8,500. He winces. "Save me, Beckett."

"What, like I do every time you won't stay in the car? You got yourself into this."

"You promised," he wails. He sounds like he's five and she's reneging on giving him a trip to the carnival. She raises her hand again, signals $10,000. He's so pathetically dependent on her saving him – and the prospect of payback is just so good - that she can't resist. The senior looks pitch blackly at her. If looks could kill, Ryan and Esposito would be arresting that woman over Beckett's cold dead corpse. Though she'd look damn good, in this dress. If she weren't dead, of course. That's a stupid thought. Focus, Beckett. It's undoubtedly the location of Castle's hand that's destroying her focus. She should take a step away. She does. And it's got nothing to do with the extremely interested expression on Martha's face. Nothing at all.

Looks like she's won. Castle's breathing sighs of relief down her neck. It tickles. She wriggles. It's nothing to do with the errant thought of how it feels to have Castle that close. Not. She'd stepped away. She had. So how come he's back right behind her again?

"Thank you, Beckett. Thank you. Did you see how she was looking at me? I haven't been that scared since you tried to kill me over the Heat name. In fact, even then I wasn't that scared." Beckett slowly raises one eyebrow.

"And you're not scared now? You owe me, Castle. Big time. You have no idea how I'm going to make you pay." He's staring down at her. Well. Down the front of her dress, again. She can see a whole book's worth of inappropriate suggestions rising in his face. She's sure they're inappropriate. A whole book's worth of inappropriate suggestions of her own wriggle down her synapses and start invading other areas.

Impropriety of any sort by any person is abruptly cancelled by a lead. Lead, well, leads (aargh!) to an arrest. Arrest leads to cells, and then, thankfully, to sleep. She'll get the dress cleaned tomorrow. No. Monday. Tomorrow is Sunday. She thinks. It all got a bit confused, what with fundraisers and auctions and then arrests. She seems to have lost a day. Anyway. Better get it cleaned. Who knows how soon she might need it again?

Now. On to a much more pleasant thought. How's she going to make Castle pay for the bid? He's already handed over the money. He'll be taking her for dinner. She's sure he'll pick somewhere nice – but she'd better make sure it's discreet. She has still no desire at all to be on page six. She'll get quite enough hazing from the entire bullpen, starting and no doubt finishing with Ryan and Esposito, as soon as she shows up. But she really does not need to be the subject of hate tweets from Castle's extremely extensive fan base. Male and female, on the evidence of the auction. Anyway. Focus. What should she claim for getting Castle out of a tight spot. Get him into a tight spot, says an evil little voice in the back of her head. Can't you think of one where you'd like him to be? That's really not at all helpful. Not one iota helpful. Several tightly clenching muscles give her the lie. She has a nice cool shower and goes to bed. Sleep is punctuated by some decidedly and unhelpfully explicit dreams as to how she might make Castle pay up. She needs another nice cool shower in the morning. She hates cool showers.

Castle was clearly brought up well. She's barely finished her coffee before he's telling her about the arrangements for dinner. Either that, or he can't wait to get rid of the obligation. Dinner, and dancing, tomorrow night. Oh. Dancing? Again? Is this really a good plan? What sort of dancing? Where? Dinner and slow dancing at a black tie establishment? How did this happen? She's the one who's supposed to be making him pay up. How does being manoeuvred into slow dancing with Castle count as him paying up? That's more – looking at his face he knows it, too – like him taking shameless advantage. Well, two can play at that game. As soon as he's out of earshot she puts a hurry-up on the dry-cleaner and arranges to pick the dress up tonight. She's been manoeuvred into that too. He's perfectly well aware she doesn't have another dress. Well, it's stunning. She's quite happy to wear it again. Lots. And the effect it has on Castle is just a happy by-product. Not the main idea at all.

"I'm still thinking about how you can pay your debts, Castle." He smiles slowly and wickedly. That's not fair. "I could make you be silent for a whole day." He looks suddenly horrified. "Or a week." There's a strangled squawk. The boys' sniggers are clearly audible. "Or you could come and clean my apartment and do my washing and cook me dinner. I've always wanted a maid. Appropriately attired, of course."

There's a very unsuppressed snort from Esposito and an even louder one from Ryan.

"Will you make him wear a frilly apron? Or a French maid outfit? How much will you pay to keep those photos off page six, Castle?" Beckett has a sudden visual brainworm of Castle in a black dress, white apron and silly little white cap and barely stops herself guffawing. Her splutters and purple face, however, don't do anything to conceal her thoughts.

Castle is impervious. In fact, he's smiling to himself. It looks very much as if a thoroughly dirty thought has crossed his mind. Asking him about it would undoubtedly be a huge mistake. It would. She goes to make coffee. Castle wanders after her. He's still got that filthy dirty smile. It gives her entirely the wrong idea about what she should have her lips on. Or he should. He looks her up and down, slowly.

"What?" she snaps.

"Just wondering…"

"What?" That was probably a really stupid question. Two seconds later, she knows it was.

"How do you know what a French maid outfit looks like, Beckett?" That's such an unfair thing to do. He is not allowed to use that voice within a hundred yards of her. Or the precinct. Ever. It wiggles straight down her spine without waiting for permission. It says in every syllable I'd like to see you dressed up. Or possibly simply I'd like to see you not dressed at all. She makes her coffee with considerably more emphasis, forceful button-pressing and cup clanking than is entirely warranted by the machine. If she's looking at the buttons the heat in her face can't possibly be attributed to anything other than the milk steamer. She never blushes. Ever. And she is absolutely not considering the benefits of dressing up. At least, not as a maid. Servitude? No way. Though having Castle at her – er – service could be really, really - No. This is not a good thought. No. It's an excellent – No! It is not an excellent thought.

She goes home as soon as it's politic to do so, picking up her dress on the way. (she strokes it when she hangs it up) Another cold shower seems indicated. At this rate, her electricity bill for this month will be halved. Her dreams are equally as unhelpful tonight as they were last night. Her morning shower is equally cold. Her day is equally full of ridiculous thoughts and speculations about how she should enforce payback. However since Castle doesn't show up, thankfully, (though she looks up – it's not hopefully, it's not - every time the elevator bell pings, which does nothing for her concentration) there's nobody to notice if she's just a little flushed. Just as well it's another paperwork day. Frequent lapses of concentration don't matter so much.

Before she gets home her phone chirps with a short text. Car will collect you 7pm.

Love to know your thoughts.

Totally frivolous fluff. There will be a total of four chapters - see, I can write short!