Hi All, this is my very first Castle fan fic. I have a lot more ideas, but this one felt like a good place for me to start. I am writing this story from the perspective that Josh is not in the picture for Beckett - for the sake of where this story goes and to keep her integrity, we assume that Castle and Kate are both completely single while in LA. I do not have plans to continue this story, I wanted to write a one-shot and see what people thought. Please let me know if you like it! PLEASE NOTE: This is for mature audiences only, it has an NC-17 rating for both sexual content and language.

Kate stands just inside her room in the hotel suite. She falls back against the door and sighs heavily. She runs her palms over her face and up through her hair. What just happened? She's fighting every fiber in her body right now to run back out to Castle and kiss him with all that she has. She knows that her reluctance doesn't come from a fear of rejection, it comes from the fear of letting herself fall, only to later lose him.

She flew out to LA to investigate Mike Royce's murder. Coming here after being advised to stay away from the investigation was a risky move, but she couldn't stay away; she needs to find justice for Royce. She knew that Castle made up an excuse to be able to tag along, but there is a part of her that is glad he is here. Sure, he is a handful, an annoyance, but even she will admit - to herself, never to him - that it is comforting to have him here.

So many feelings have surfaced during this trip to the west coast. Feelings for Royce; feelings for Castle; feelings that have her questioning what is most significant in life, especially to her.

Her mind drifts back to just a few moments ago. She sat in the suite lobby twirling her fingers in her hair, shamelessly flirting with Castle as he revealed that she was the mystery he thought he'd never be able to solve. He told her how amazed he was by the depths of her strength, her heart…and her hotness. Leave it to Castle to infuse humor into a heartfelt sentiment.

He has such a wonderful way with words, he is a writer after all, but she truly loves how his words make her feel. She knows that no matter how cheesy they might be, they are genuine. He thinks the world of her, and cares for her more deeply than she can comprehend. This scares her in so many ways. She is in love with Castle, but she suppresses her feelings for him in an attempt to make them go away. Although her mother's murder happened more than 10 years ago, the pain is still so raw, so fresh. She knows another loss of that magnitude could shatter her very existence. But still, there is hesitation. Castle knows her so well, even better than she knows herself at times. Maybe he is different. Maybe he won't become disinterested in her. Maybe he won't leave. Maybe...

There's an electricity between them, even she can't deny it. The longing is evident in both of their eyes. Just five more seconds, maybe only three more seconds, who knows what could happen. Instead of finding out, Kate does the only thing she knows how to do; she evades. She knows how Castle feels about her. Anyone who doesn't know by now is clearly not paying attention, but she couldn't act on it. She is so afraid. She knows if she lets Castle in, that will be it. He'll fracture the wall eventually. He's the one person that can break her, and it scares her to death.

Shaking her head, and bringing herself back to the present, she takes a deep breath. Slowly, she reaches for the door handle. Her hand sits idly on the knob, but does not turn it. She's trying to rationalize her fear, but it's been so long since she's let herself even think about someone in this way. Maybe now is the time, maybe now she needs to let herself feel again, to love, truly and without reservation. It's risky, but she's tired of hurting; she's tired of hiding. Traitorous thoughts begin flooding her mind. What if? What if she tries, it could be great. He could make me believe in love again. She closes her eyes, and before she can process what she's doing, she begins to turn the knob and step through to the common area. It's too late to go back now. She slowly lifts the lids on her eyes as she pushes the door open the rest of the way. Castle is still sitting on the couch. He hears the door open and his head snaps up, his eyes meet hers.

"Kate, are you ok?" he asks, concern evident in his voice.

She doesn't answer him. She feels as if she's lost all control over her own body. He stares at her, his head following her every move as she slowly walks over to where he's sitting on the couch, and sits down next to him.

He begins to speak again, "Kate, I...", she quickly puts one index finger over his lips, a silent plea to quiet his words. Their eyes stay fixed on each other. Castle gently takes her hand and slowly brings it to his heart.

Kate brings her other hand up to Castle's cheek. She begins to softly stroke his stubbled cheek and chin, never taking her eyes from his.

Castle decides that he is going to take the leap. She's been rejecting him constantly up until this point, what's one more rejection if she's not really thinking what her actions are clearly conveying? He closes his eyes and unhurriedly begins to lean in towards Kate; his lips calmly searching for hers. Kate closes her eyes and slowly begins to move forward. She can feel his chest pounding against her hand. She can't help but smile. As they inch in closer, she begins to feel his breath on her skin. Her heart is beating rapidly in anticipation of feeling Castle's lips on her own.

It feels as if time stops when lightly, their lips touch. The kiss begins chaste and simple, but after a few short seconds, their lips part in unison, their breath ragged and full of want. Castle begins to run his tongue across her bottom lip, his breath catching as he realizes who he is kissing. Beckett opens her mouth and allows Castle's tongue to dance with hers. She gently bites his bottom lip and then smoothly runs her tongue across the spot she just nibbled. Castle lets out a moan, clearly turned on by what Beckett is doing to him with her mouth. He moves his free hand to the back of Kate's head. He runs his fingers through her hair and holds her head steady to his. Their kisses become more passionate and intense as nearly four years of tension and anticipation melt away.

As the need for oxygen arises, they break the kiss. Their foreheads touch, eyes remain closed, and their breathing is shallow and heavy.

"Wow," Kate says, trying to steady her breathing.

"I know," Castle stutters.

Kate begins to unbutton Castle's shirt, but as she struggles with the second button, Castle grabs both of her wrists and pulls back to look into her eyes. His eyes are dark and filled with lust, but a look of uncertainty flashes across his face. Kate looks at him with a hint of embarrassment and surprise. She isn't sure what to think. Does he not like it?

"Kate, I can't do this if this is just going to be a one-time thing. I...I'm so in love with you Kate, and it would kill me to be with you like this if it doesn't mean the same to you as it does to me," Castle looks into her eyes, baring his soul.

Kate smiles, and then sighs. She bends forward so that her forehead is resting against his. She closes her eyes and, despite her fear, tells him exactly how she feels. "Castle...Rick, I know I haven't made this easy for you, for us. I've been stubborn, scared, and resistant to taking our relationship to the next level. I made a decision tonight to let you in. This is huge for me, I'm terrified Castle, I'm afraid of letting you in only to lose you. I love you too, so very much, and I don't want this just for tonight. I want to be with you for as long as you'll have me."

Castle is stunned by what he is hearing. He's grown accustomed to Beckett being so closed-off, careful with her heart, and so very private. She's finally letting her guard down and sharing her feelings with him. She's risking her heart for him. For once, Castle is at a loss for words.

He releases her wrists and pulls her in close to hold her. She snuggles into him and can't help but grin from ear to ear.

"Kate, I'm speechless. I mean, do you know how long I've waiting for you to trust me with your heart? I will never intentionally hurt you Kate. I want to take care of you. I want to be here for you, whenever you need me, always" Castle expressed.

"Good, well since it seems we're on the same page, are you ok with this now, or are you going to push me away again?", Kate chuckles, pulling herself back from his chest to look into his eyes.

Castle's expression relaxes, and suddenly Kate stands up. She pushes Castle back against the couch and straddles his hips. Grabbing the bottom hem of her shirt, she pulls it up and over her head and throws it to the floor.

She captures his face with both of her hands, presses her lips into his, then lightly bites his bottom lip again, knowing that he liked that gesture from her earlier. She glides her hands up the sides of his face and gently clenches his hair in her fingers. She begins kissing his neck, peppering his jaw with wet open-mouth kisses, and sucking gently on his earlobe.

Castle's hands snake around her waist and he begins running his hands all over her soft skin. Up her sides, down her back, and then he moves his hands over her pants, cupping her ass.

Beckett grinds her hips into Castle's growing erection. Castle can't take it, she's driving him insane.

Castle scoots himself forward so that he can stand. He places his hands under her thighs to support her as he stands up. Kate reaches her arms around his neck, and nuzzles her face into his ear. She wraps her legs around his waist as he stumbles to his side of the hotel suite.

Castle fumbles around once he reaches the door to his room trying to find the knob. Once he's found it, he turns the handle and kicks the door open with a thud. He walks them over to the bed and gently lays Beckett down on her back as he hovers over her, placing most of his weight onto his forearms. He breaks their kiss to gaze into her eyes. She looks amazing. Her hair is splayed out on the pillow, her cheeks flushed, her eyes burning with lust.

Slowly Beckett reaches up and begins unbuttoning Castle's shirt again. She watches her hands work down his shirt while his eyes do not leave her face.

"God Kate, you're beautiful," he confesses.

"You're not so bad yourself Castle, but you're wearing too many clothes at the moment," she says with a devious grin.

"Let's see what we can do about that," he responds, his breath catching in his throat as her fingers brush over his shoulders to push his shirt off of him.

He wraps his arms around her back and lifts her just enough to unclasp her bra. She shimmies her arms and shoulders to help him remove it completely, and she now lays there naked from the waist up in front of him. She feels a bit vulnerable, but she trusts Castle.

Slowly, Kate moves her hands down to his waist. She runs one hand over his length through his jeans. He closes his eyes and takes a deep breath as she teases him. She deftly unbuttons his pants, slides his zipper down, and hooks her fingers into his belt loops. She adeptly pushes his pants down his legs, taking his silk boxers with them.

As his erection springs free, her eyes get wide, and she lets out a small moan.

"Oh god Castle. I had my suspicions, but wow," she says, impressed by his endowment.

He smiles down at her, his eyes crinkling at the edges.

She grabs his hard length with one hand and begins stroking it, applying just a little bit of pressure. With her other hand she tickles his scrotum with her fingernails.

"K..Kate," Castle chokes out. "I love what you're doing to me, I do, but if you keep that up, this will be over before we even get started, and that's not what I have in mind for you, for us, tonight."

She moves her hands up to his face, cupping his cheeks. She looks into his eyes, taking in the gravity of what she is about to do with him.

"Castle, make love to me. I want to be with you tonight, in every way," she tells him, her eyes blazing with desire.

His mouth is on hers in an instant. He lets some of his weight off of his forearms, and he begins to grind his erection into her pubic bone, putting the perfect amount of pressure into just the right spot. She still has her pants on, but by the noises she is eliciting, he is pretty sure that she's liking this.

The room is hot, they begin to sweat, and their breath turns heavy and harsh. Their tongues duel as their kiss deepens and becomes more passionate and eager.

Castle breaks the kiss and begins pressing wet, open-mouth kisses along her jaw. He finds a spot, just behind her ear that seems to drive her crazy, but he decides to revisit that a little later. For now, he continues his journey down her body. He begins to gently massage her breasts and takes one of her nipples into his mouth.

She gasps at the sensation of his tongue circling her nipple, flicking back and forth across the hardened peak.

"Oh god Castle, that feels soooo good," She breathes.

Suddenly his mouth is off of her, and moving down, down, down to the place he most desires. He props himself up on his knees and hooks his fingers into the waistband of her pants. He slowly slides them down along with her panties, and pulls them over her feet. He discards them on the floor, and begins kissing up her calves, and then her thighs.

They are both completely naked, finally. Castle gently takes one finger and runs it down the inside of her folds. Beckett arches her back in response and lets out a pleasing growl.

Castle slowly moves his head down between her thighs. He pushes two fingers into her depths while placing his tongue inside of her folds. He begins to taste every bit of her. He finds her clit and circles his tongue around it. A satisfying moan comes from deep in her throat that takes Castle's arousal up a notch.

He gently curls his fingers and begins pumping them in and out of her. His tongue making deliberate movements over her clit, and around her folds as she groans in pleasure.

"Castle, this feels amazing, I'm so close, but right now I want you. I need you inside of me." Kate begs, her voice desperate. "Let me ride you, I want to be on top, please Castle, let me feel you deep inside of me."

He didn't have to be asked twice. Castle smoothly rolls to his side and turns them over so that he is now on his back, and she is hovering above him.

Kate takes one leg and swings it over him, straddling his hips. She moves forward and feels his throbbing erection at her entrance. She slides back and forth over him, running his length in between her folds, teasing him, soaking his shaft in her wetness.

"Kate, oh god, that feels so good, but if you don't put me inside of you now, I'm going to have to take over," Castle warned.

Beckett tilts her hips slightly back, and slowly pushes herself down on his length. Down, down, down, she sinks onto his cock. Every pleasing inch filling her more and stretching her to her limit. They let out simultaneous groans as they join as one.

"Oh my god, oh my god, oh my god," Castle repeats over and over. Still reeling from the fact that he's making love to Kate - his Kate, after nearly four years of chasing her.

Kate begins to ride him, she moves her hips back and forth, and uses her legs to lift herself up and then slide back down onto his cock. She brings her hands up to her breasts and begins playing with her nipples. Castle's mouth drops open at the sight of her touching herself.

"Kate, I can't hold on much longer, you're driving me insane," Castle moans, holding back with everything he has so that she can cum first.

"I'm so close Castle, so close," she breathes.

"Cum for me Kate, I want you to let yourself go for me," Castle says through gritted teeth, trying to stifle his own climax.

"Oh god, Castle, oh god, Rick, oh god, oh god," Kate screams. Her walls tighten around him and she shatters. She doesn't hold anything back. She lets herself go completely. She puts her hands on his chest as she rides out the waves of her orgasm.

Castle watches as she comes down from her high. He slowly turns his torso, while his hands rest around her back, and skillfully turns them so that he is now on top again, and she is laying on her back. She looks up at him and smiles.

"That was smooth," she tells him, impressed by how effortless he was able to move them around.

"I need to be as close to you right now as I can. I need to feel your skin against me, your heart beating, and your breath on my cheek," Castle confesses as he looks into her eyes.

He captures her lips with his, an electricity sizzling between them. He breaks their kiss and looks at her while gently swiping his hand over her forehead, pushing a few locks of hair out of her eyes.

"You're the most amazing woman I've ever known. I will never get enough of you, enough of this. I want to share everything with you Kate," Castle professes.

Their hands find each others' above her head, and their fingers intertwine. Castle closes his eyes and lays his forehead against hers. He slowly begins moving in and out of her. He pulls himself almost all the way out, and then glides back in, slowly, deeply, as deep as he can. She moans at the sensation of him filling her. He growls at how good this feels, being inside of her, the woman he's been in love with for so many years.

"I'm close Kate, are you still ok with this?," he asks her, making sure she is ok with what they've started.

"Rick, I want to feel you cum inside of me," Kate confides.

He smiles and begins to move faster, his forehead still gently pressed against hers; his breathing hot against her lips. Their eyes are closed as they both revel in the feel of each other.

"Oh god, I'm...oh Castle," Kate screams, as her walls clench around his shaft, she tightens her grip on his fingers, and her entire body stiffens as another orgasm overtakes her. Twice in one night, she's never had that happen before.

"I love you Castle," she whispers to him, still continuing to feel the after shocks of her second climax.

This is all it takes to send him over the edge.

"Kate, fuck, Kate, oh god, Kate, mmmm," Castle pants, as he shatters; and suddenly he explodes inside of her.

He trembles as he comes down from his apex. His breath is uneven, sweat glistening on his forehead, and slowly, he captures her lips again. He kisses her sweetly, taking his time, enjoying the feel of his mouth on hers, her breath mingling with his.

"Oh my god, Kate, what...how? I know this sounds corny, but I've never had one that intense before. God, you're amazing," Castle tells her as he takes his right hand away from hers to stroke the side of her face.

He slowly slides himself out of her and rolls off to her side. He lays on his back and she cuddles up to him, laying her head on his chest. She lightly strokes his side with her fingernails. He brings his arms up around her, drawing small languid circles on her back and kissing the top of her head.

"I love you Katherine Beckett," Castle smiles.

"I love you too, Richard Castle" Kate breathes out with satisfaction in her voice.

Kate is exhausted. It's been a long day. There is more to investigate tomorrow, and a lot to think about in regard to the changes in her personal life. She smiles as she thinks about the giant leap she has taken with Castle tonight.

She begins to ponder what this change in their relationship might mean. What implications it could have; especially in her professional life.

"Castle, please don't take this the wrong way, but I think we should keep this between us for now," Kate yawns.

"I understand Kate; I think that's a good idea. Besides, that just means I get to keep you all to myself for a while," Castle concedes.

"I like that." Kate says, now barely able to keep her eyes open.

"Me too. I love you," Castle breathes.

"I love you too Castle," Kate replies.

"Good night beautiful," Castle tells her as he kisses her temple.

"Good night love," Kate mumbles as she drifts off in his arms.

Tomorrow she'll worry about how to handle the details of where this leaves her professional relationship with Castle. Tonight, she is going to enjoy being in his arms, loved, and safe, feeling happier than she has in years.