(Please note the rating change to M)

Kate's hand falls to his face, and she rubs the backs of her fingers along his smooth, masculine jaw, never breaking eye contact with him as the danger outside becomes tangible.

She tries to convey to him through her soft look, her gentle touch that he means so much more to her than just a partner, and as her thumb outlines the swell of his upper lip, Kate trembles at the knowledge that this searing connection she feels towards him just might be the very last thing she feels on earth.

Castle's hyperaware of his surroundings.

Kate's cherry essence is surrounding him, infiltrating every pore of his skin. His body hums with pure need from having her enticing curves intimately entwined with his.

He's always known that the chemistry between them was palpable, but bloody hell, he almost feels like an out-of-control virgin with her questing fingers leaving a trail of fire wherever they touch.

His mouth tingles from her insatiable, demanding kisses and his lips literally yearn for the taste and feel of her creamy skin once more.

He's surprised when a deep fear settles into his bones… Surprised that it's not the fear of being discovered and the chance that he'll end up as doggy kibble… He's suddenly afraid that now that he's tasted her, Katherine Beckett will become an incurable addiction.

His thigh is placed at the apex of her thighs, on the tight seam of her jeans, and when she exquisitely grinds down, his member jumps in response, aching to be encased inside her wet warmth.

But dammit, Fang is sniffing around their hiding place… Castle can just imagine the slobbery hound snarling triumphantly as he discovers them.

He holds perfectly still with Kate wrapped in his long limbs. He's poised, alert, expecting any second for the crawl space hatch to be opened and for them to be discovered.

He clenches his teeth together as his hands instinctively cling tighter to her curves. There's no way in hell that that rabid dog is getting his teeth into Beckett. He's prepared to kick off the dirt wall and curl his upper body around her head and shoulders to protect her. He knows this will expose his neck and back to the vicious animal, but it's a small price to pay.

He already made the decision a long time ago, that if it was necessary, he'd take a bullet for Detective Kate Beckett and do so gladly, without a second thought… He'd already demonstrated that determination at Roy Montgomery's burial, so the possibility of a sneering dog attacking him pales in comparison.

He looks down into her mesmerizing tawny eyes.

God, she's exquisitely beautiful with fly-away hair, swollen lips and bright pink cheeks, - all a testament to their frenzied love-making.

He can hardly believe that after all this time, almost four years of longing for her, fantasizing about how she would feel beneath his hands, beneath him, that at this most inopportune dangerous time, she made the first move and decided to take their partnership to the next level. He chuckles internally as it seems par-for-the-course, - so natural and fitting for them.

As Fang sniffs just outside the crawl space door, Kate's eyes soften and seem to glow as she stares boldly at him. Right now, she's more open to him than she's ever been before in her life… His heart literally skips a beat as he sees in their depths something he thought he'd never encounter, – a promise of a future for them.

He's breathless when her fingers drop from his hair and travel along his jaw line, her touch giving him hope in this impossible, scary situation that realistically, they might not make it through.

He's lost in the depths of her eyes as her thumb traces smoothly the outline of his lips.

Kate's exposed, bare, her feelings on full display for him to read, … and shit, he's as hard as steel with her staring at him with raw hunger and blatant desire like she's having difficulty controlling herself.

The sexual tension zings throughout the tiny space, - edgy and fierce, - and combined with the adrenaline rush, Castle thinks that he just might explode from the overwhelming sensations bombarding every facet of his body.

Her thumb stops moving as Fang suddenly yelps from being jerked back by his collar.

Kate anxiously waits with bated breath the outcome of their predicament, trying to portray through her eyes just how much she cares for him, how much she wants him, wants this.

She mouths, "We're going to make it," just before they hear, "Roman, get up here! Looks like the Fuzz found us."

Her sweet breath releases over his mouth, - gentle, soft as a feather, tickling his senses with hot vanilla late topped with whipped cream and it brings to mind a fantasy of him pouring luke-warm expresso into her belly button and then sucking to his heart's content, feeding on her milky skin.

He groans internally as that thought certainly doesn't help his current situation with his racing heart and pounding blood, as now he instantly needs some relief for his sexual frustration.

They hear Roman and Fang tramping up the stairs and he barely releases a sigh of relief before her lips are ghosting over his, breathing him in, sharing the same air. She catches his exhale and harshly huffs out his name, all desperate and needy and so un-Beckett-like.

He shivers as rippling heat flows through him at her passion-rich tone. The sweet heat of his name flows over her lips and through his mouth and fires through his veins, twisting his gut in torturous longing.

The deep sweep of her lashes call to him and then he's lost to everything else but her words as she says huskily, "We don't have much time, and – and I neeed this."

She falters over the word 'need,' inciting the flame within him to an uncontrollable inferno that threatens to consume him with each and every powerful breath she takes.

"I need you," purrs past her lips before they're crashing into his, - fluid, fierce, flaring with passion, - wreaking havoc on his mind and body.

It's her next move though that solidifies this is real. This is actually happening with the woman of his dreams.

He doesn't know how Kate does it, (but attributes it to hours of yoga classes) as she's suddenly untangled herself from his limbs and he's flat on his back, and Beckett, Sweet Jesus, is on top of him, her body undulating sensuously.

She's all lush legs and full breasts and vixen smile as sprinkles of dust float from the ceiling and fall to the ground around them.

She nips at his lips as her pelvis dances with his pulsing erection and Fuck, her hand is between himself and her and she's doing something wickedly erotic that has him right at the edge, teetering on a rocky precipice, swaying towards the eternal abyss.

His right hand encompasses her small breast and kneads the firm flesh through her brassiere; his thumb easily finding the erect nub and scraping the lace torturously along her nipple.

She moans so deliciously, so salaciously at the contact that Rick can't stop himself from bucking his hips up into hers. Kate flicks her hips and clenches her upper thighs and it's the last straw… It undoes him, U-N-D-O-E-S the roguish, ruggedly-handsome, play-boy millionaire known as Richard Edgar Castle.

He breaks under the lure of her siren's spell... He's gone, - all liquid fire shooting through his manhood as her mouth grazes hotly along his jaw.

"Fuck, Castle!"

His orgasm triggers hers and she's thrown over the cliff and into a cataclysmic freefall of ecstasy, - the magnitude surpassing any other sexual experience she's had before.

She haunts his senses as her body bows in ecstasy… Her teeth bite into her lower lip as she tries to curb the mewling sounds created by her intense, earth-shattering orgasm.

Kate lays perfectly still on top of him while coming down from the overwhelming high, trying to regain her sense of sight as stars continually shimmer across her vision. Tremors run through her body as after-shocks continually assail her.

His large palms cascade up and down her back soothingly, lovingly. His writer hands tell her without words just how affected he is by what happened.

She revels in the sound of his thundering heart slowing down, revels in the movement of his strong chest easily able to hold her weight as she slowly comes back to reality. She can't help thinking that if this is what happens being fully clothed with Rick Castle, she just might not survive him in the actual flesh.

"If I would've known that you'd be this affected by me, Detective... I would've devised a plan long ago to have us both imprisoned in a very tiny room."

"Mmm," she hums, seeming to have lost all coherent thought. "I may have seriously hurt you if you had planned out this scenario earlier."

She looks into his impish eyes while a lopsided, sheepish grin spreads across his face. She slaps him playfully. "And NOT in a good way."

His laughter is deep, throaty and shakes her to the core, making her wonder whether he prefers a woman in bed, on the floor, on his desk, against the wall, in his car, or in the shower… (Gawwd, she can only imagine how talented his writer's hands are in the shower) And she determines to find out the answer to that question this very day.

"You know me too well."

"I certainly do know you," her eyes twinkle devilishly, "But I'm looking forward to getting to know you even better."

There's a noticeable pause before Castle responds.

"Reassure me, Kate," he says seriously with a hint of nervousness in his tone, "That this is going to happen again."

She places her hands on his chest, elbows out, her middle fingers touching one another so she can rest her chin on her hands and look up into his face.

His face, blissfully sated from their love-making, also shows a sheen of apprehension, wondering if this is truly real.

She smiles at him teasingly. "Oh, I don't know if I can promise that this will happen again, Partner."

His eyes falter as her words prick at his heart strings, but she quickly continues, "I can't promise another ummm," she licks her swollen lips, "dry-humping session, but I can promise you that next time, ... the only thing I'll be wearing is my Birthday suit."

That smarmy, cocky grin of his surfaces that screams, 'I'm-a-sexy-very-skilled-man-and-I'd-be-happy-to-p rove-it-to-you'… The one that causes her stomach to flip-flop every damn time.

"Birthday suit, huh? Can I have the privilege of helping you to change into that suit?"

"That can definitely be arranged on one condition."

"I don't know if I like the sound of that."

Her answer though has him literally gasping for breath and drooling at the same time, thinking nasty thoughts of making her 'come' again, - ImmEdIatEly.

"I'll let you help me only if you're a very bad boy, Rrr - icky." She trills the 'R' in his name and it certainly has the effect on him she's looking for.

His eyes darken to orbs of lust as another piece of the Beckett onion is revealed.

"OH, I'm happy to show you just how bad I can be, Beckett," and his hands eagerly seek the top button on her skinny jeans all hot and urgent and him. "Any day, any time, any place you want, ... and I'm going to start right now."

She gasps as his thick fingers skirt beneath the denim and slide beneath her silk, wet panties. Kate's last coherent thought is, 'I really had no idea."