Kate Beckett closed the door to her room, again, her left hand lingering on the handle and her lower lip caught between her teeth. She had been that close to sleeping with Castle. Fuck. Sure, all she had done was open the suite door, to return to where she had left him on the sofa. But there was no doubt in her mind that a step into the hotel living room would have effectively pushed the domino that she had worked so hard to keep upright.

He would have stood; she would have opened her mouth to speak. He would have taken careful steps toward her; she would have looked at him with permission flowing like teardrops. He would have pushed her up against the wall; she would have reached up and run a hand through his hair. He would have pressed his lips to hers and sought entrance with his tongue; she would have opened her mouth and taken it hungrily. He would have guided her to her bed; she would have lain before him in blissful submission. He would have undressed both of them; she would have shivered in anticipation. He would have glided into her in one smooth stroke; she would have surrendered to love.

Instead, Castle hadn't been there at all, retreating to his room to give her the space she had obviously wanted when she ran scared. A potent mixture of gratitude and disappointment sat heavy in her chest, making it hard to breathe. She had a boyfriend. A goddamn saint of a boyfriend, who did his best to love her from the shadow cast by a ruggedly handsome writer. None of this was fair to him (was it really fair to any of them?) and she would have to end that relationship before anything with Castle could be right. Then maybe, maybe, she'd be strong enough to fall.

Decision made, Kate sat down on the bed, tucking her feet under the covers and propping herself up with a few of the fluffy hotel pillows. She turned on the TV, but nothing was interesting enough to distract her from the lasting memory of the way Castle had looked at her when he described her as a mystery he was never going to solve. Tapping the power button, she tossed the remote away and sighed. She needed her best friend, the man who thought she was extraordinary even on the days she knew she wasn't. Desperate, she did the only thing she could think of…she picked up her phone from where it had been charging on the nightstand and called him.

"Detective?"

"Um…Hi, Castle…I just…I thought maybe we could talk." God, was she twelve? Calling a boy shouldn't be that hard. Ugh.

"Ok, sure. But weren't we just doing that a few minutes ago?" She sensed the smallest of smirks from him, but could also tell that he wasn't looking to tease her. As much as she gave him shit, he really did know when to be serious, especially where her feelings were concerned. He'd let her take the lead in this conversation.

She cleared her throat. "Yes, but I know I left kind of abruptly. We were having a nice time. Well, I mean, I was having a nice time. Really, I'm glad you're here with me and I just wanted to say thank you."

"You don't ever have to thank me for being your friend. And, to be clear, I was also having a nice time with you." He paused, unsure whether he should go on. He decided against it and just listened to her breathing on the other end of the line. Honestly, he had mastered patience for Kate Beckett long, long ago.

The silence was finally broken by an expected admission.

"I opened my door. After I left you. I opened the door to go back to you, but you were gone."

"You…you…came back?" His surprise was evident and his stammering made her feel oddly better. As if she weren't the only one being overrun by nerves.

"Mmmhmm."

"But, why?"

"To push the domino."

He laughed. "Ok, you've officially lost me."

She fought the instinct to mumble nevermind and just hang up. But there were two closed doors between them and somehow that made her brave enough to continue. "Castle, something was happening during that conversation. And…I think more was about to happen. Between us. But it scared me and I ran. And you've been observing me for long enough that I don't think any of what I'm saying is something you don't already know."

He ignored the truth of her last sentence. "So, after getting scared, you changed your mind about running away. And you decided to open the door, to let that action be the catalyst for whatever was about to happen between us. To push the domino, as it were."

"Yes."

"And yet, here we are, having a phone conversation just two rooms away from each other, instead of talking face to face.

She sighed. "Yes."

He allowed the quiet to envelop them again, until she got her bearings. "When I saw that you had already gone to your room, I came back in here. And I realized that I've completely disrespected my relationship with Josh. This isn't all about me and I need to break up with him before it's okay for me to go looking for what I want."

"And what do you want, Kate?"

"You."

One simple three-letter word, yet it reverberated throughout the suite, its effects tearing into them both so deeply that neither could breathe. Kate had stunned herself with the blunt confession (though it was obviously where the entire damn dialogue had been heading) and she was frozen in place, waiting to see what he'd say. She heard him take a deep breath, then exhale, as if he were practicing yoga instead of listening to her acknowledge this thing between them.

He could have taken the conversation anywhere at that point. He could have asked her how quickly she'd end things with her boyfriend. Or for more details about how much she wants him. Or even why they couldn't just screw it all and jump into bed, since the emotional affair had already begun. But really, Castle had always been careful (cowardly) about pushing her on this issue. And if she were willing to tiptoe toward him, she knew he'd accept that.

"Kate?"

"Yeah?"

"Do you want to keep talking? Or do you want me to let you go to sleep now?" He was ready to camp out on Rodeo Drive, wait for Tiffany's to open, buy her the most perfect engagement ring, and live happily ever after. She probably wasn't on the same page quite yet.

"Honestly? I want you to come to my room. Which isn't fair to you, I know. But I just want my best friend."

He ended the call. Moments later, she heard the knock at her door, soft but sure.

Her heart pounding, she got up to answer it. As Kate opened the door, an unexpected tear rolled down her cheek. He stood in front of her and, with a look of utter adoration (love?) on his face, he reached up to wipe the tear away. Then Castle stepped forward to wrap his large body around her trembling one, placing a chaste kiss on the top of her head. He had changed into a t-shirt and sweatpants and the whole scene was so domestic and intoxicatingly tender. She stayed in his embrace for several seconds, finally breaking away to look at him with glistening, grateful eyes. She ran her hand down his chest and slightly shook her head, shocked that they were actually here. After years of partnership, she had admitted real feelings, and yet they were going to do nothing about it. The whole situation was an odd, sweet torture. Her hand eventually found his and she tugged him toward the bed.

She crawled back under the covers and moved over enough to give him room. He seemed to hesitate for a moment (but wasn't that exactly why he was there?), until he finally joined her. She turned her back to him, then reached back to wrap his arm around her waist. He cautiously allowed it, but maintained a safe distance. Space wasn't at all what she wanted, so she pulled him against her and simultaneously scooted back into his warmth until, oh, oh…that's why he wanted room between them. Wow, she really wasn't being reasonable at all.

"I'm so sorry." Any developing tension was broken when they apologized at the exact same time.

"Kate, what on earth are you sorry for?"

"Um, for putting you in this position. Why are you sorry?"

"Because I didn't really want you to feel me in this 'position.' But clearly my brain and body are not on the same page."

She wasn't about to admit that it felt reassuring, knowing that he wanted her in such a primal way, and that it sent a rush of blood to her center. She simply held him tighter to her and ran her finger up and down his arm. His thumb rhythmically caressed her over her shirt, just under her breast, soothing and erotic at the same time.

Just when he thought she had drifted off to sleep, she whispered in the darkness. "I'm scared, Castle."

"Of…?"

"Screwing this up. Screwing us up. You've been so patient and waited all this time for me to be ready, and I'm terrified that I'm going to make a mistake and push you away."

He leaned forward to kiss the back of her head, staying there to nuzzle his nose in her hair. "Kate, sweetheart, you will make mistakes. You're extraordinary, not perfect." A tiny smile escaped her. "But I'm not going anywhere. For now, I'm your friend. And I want to be so much more than that, when the time is right. I will hold you through all of it and we can be terrified, ecstatic, sad, angry, frustrated, and hopeful together."

She turned in his arms long enough to kiss him on the cheek, then rolled back over, spooning again. "Goodnight, Castle." Once she closed her eyes, she was able to relax into sleep…he fell soon after.

It had been two weeks since that night in Los Angeles, where their dreams became one amidst their careful embrace. Kate had called Josh as soon as she returned to New York, met with him, and ended things as smoothly as possible. He was a smart man and it didn't take more than a few words from her to make it clear that she had finally opened her eyes (and her heart). Josh simply nodded, wished her the best, and walked away. He couldn't possibly fight for something he never had.

If anyone had asked, she would have sworn that she'd fall into Castle's arms immediately after her breakup. That the magnetism between them would have made it impossible to stay apart any longer. Instead, she spent a quiet night at home with a glass of wine and her thoughts. And in the several days since, he had kept his distance with a comforting smile, allowing her the freedom to make the first move.

Now, they were in her car, headed back to the precinct after interviewing an office full of potential witnesses. She reached across to put her hand over his on his thigh, squeezing lightly.

"Would you like to come over tonight? Maybe bring some dinner?"

Castle's grin answered for him. "In the mood for anything in particular, Detective?"

"Surprise me."

They left the precinct a few hours later, going their separate ways in the lobby. She hurried home to shower, changing into yoga pants and a soft shirt. Once she was dressed, she found herself pacing nervously, as if he hadn't been over to her apartment a million other times. Calm down, Beckett. It's just Castle. You're having dinner and you know he won't push anything else if you don't want him to. But perhaps that was the issue…she absolutely wanted him to.

His arrival startled her and she hurried to answer the door, finding him there with a pizza box and a bottle of wine. She stepped back and waved him toward the kitchen, then followed behind him to get plates and wine glasses. She realized they hadn't even spoken when he nudge her hip with his.

"Hey."

She burst out laughing. "Hey yourself. This smells amazing, thank you."

They brought everything out to her coffee table and sat next to each other on the floor. The fresh mozzarella and basil was heavenly and Kate momentarily let herself get lost in the simplicity of eating pizza in her apartment with the man she loved…oh, there were the butterflies again. Castle seemed to sense it and launched into a story about some friends of his getting busted in high school while pulling a senior prank. Between the easy narration, his reassuring eyes, and his charming smile, she finally put everything else to rest and stopped thinking so much. They were here and she was happy.

When they were finished eating, Kate took the plates to the kitchen sink and began to rinse them off. He came up behind her and threaded his arms through hers to help, his breath warm on her neck. She shivered and reached for the dish towel to dry them both, delighted at the feeling of his body still pressed against hers and moaning when he dipped down and kissed her in the soft spot just below her ear. Her head tilted to the side, allowing him more room, and he nipped at her earlobe before dragging the tip of his tongue along the smooth skin bared to him. Castle's large hands found her waist and moved under the hem of her shirt, holding her there.

She was filled with indescribable warmth and couldn't help but move her ass back into him, feeling exactly how ready he was for this to happen. His groan was superfluous confirmation, but it was the trigger to her turning around and crushing her mouth to his. Kate licked along his lower lip, seeking an invitation for more, and finding it easily. Her hands found purchase in his hair, bringing him as close as possible, and her tongue danced with his as if they had been doing this for years. They were so hungry, so tangled in each other that they didn't pull away until they were gasping for breath. Even then , they rested their foreheads against each other and shared the same air.

Her hands fell from his head and she hooked a finger in his belt loop. "Come on, I don't think we need to do this in my kitchen." Kate dragged him down the hall (as if he wouldn't have gone willingly), kicking the bedroom door shut once they were inside. From there, everything seemed to move in slow motion. Her mouth met his for a deep, yet tender kiss, as she worked to unbutton his shirt. As soon as she was able, she slid it down his arms and tossed it to the side, kissing his newly exposed chest. Her hands ran from his shoulders to his hands and back, bringing goosebumps to the surface. She then unbuckled his belt and unfastened his pants, until she could push them down to his ankles. He kicked them into the corner and removed his socks. Now that he was wearing nothing but his boxer briefs, she couldn't resist the temptation to look down at him.

Castle tipped her chin up and pulled her close for another kiss, ready to undress her with the same gentle care. He dragged her shirt over her head, eyes drawn to her uncovered breasts, her taut nipples beckoning him. He cupped both breasts, running his thumb over one tip while taking the other in his mouth and sucking softly. Kate's head fell back with a moan, the coil of heat in her belly intensifying as he tugged the waistband of her pants over her ass and down her long legs. She was completely naked in front of him, but blanketed in love, reminded of it as her kissed her thoroughly and walked her backward to her bed.

She fell onto her back, her legs still hanging off the side of the bed until he lifted them over his shoulders. Kate held her breath in anticipation, gasping when the flat of his tongue connected with her center, drawing the wetness from deep inside her up to her swollen clit.

"God, Kate, I have wanted to taste you for so long." His candid words, combined with his ongoing ministrations, only served to increase her arousal. Castle alternately nipped, sucked, and licked her, all with the perfect amount of pressure. She lifted her hips into him, eager for as much as he would give. When he added his hands, spreading her apart with one and inserting two fingers from the other, she chanted his name reverently. In response, he began to curl his fingers, pressing against the spongy part of her wall, and worked her zealously with his mouth. Damn, how did he get her there so fast? She'd been with men who wouldn't have figured her out with illustrated instructions.

"I…I'm…Castle, I'm…" Her inner muscles were starting to spasm and he didn't slow down until she began to shatter around him. He drew his face away to watch the orgasm wash over her and eased her down with his fingers, still moving inside her. When her breathing had returned to normal (or as normal as it could get when she still wanted more of him), he kissed his way up her body and hovered above her as their eyes connected.

"You are so beautiful, Kate." He looked like he wanted to say more, but held back. She knew the feeling.

She gripped the back of his head and pulled him toward her, wanting (needing) to taste herself on him. With her tongue deep in his mouth, she reached down to palm him through his boxer briefs. His hips jerked into her and he moaned, desperate for more. Castle rolled off of her long enough to remove the last barrier between them and, before he could move back, she straddled his hips and smiled down. Kate wrapped her thin fingers around the base of his cock and rubbed it through her folds, teasing both of them. Unwilling, or unable, to keep him waiting any longer, she lowered her body until he was buried inside her heat.

She braced both hands on his chest and began to rock back and forth, letting him slide almost entirely out of her before taking him deep again, spreading her legs further apart at his sides. Kate closed her eyes to focus on the sensation of him filling her so completely; she imagined she could feel every ridge, his tip plucking her like a harp. She sped up, her moans filling the room as he stared at her in wonder. As if that weren't enough to drive her into ecstasy, Castle began circling her clit with his middle finger, the tiniest of strokes having the greatest of consequences. Her movements became sloppy as she lost control, trying desperately to keep her eyes open, to watch him watch her. She came with a violent shudder, her body clenching tightly around his with a primal instinct to hold him where she needed him most. As Kate fell forward, he grabbed her hips, doing his best to maintain some sort of rhythm, prolonging her orgasm.

The spasms subsided and he took the opportunity to roll them over, pressing her into the mattress. He wasn't going to last much longer, but he wanted to be as physically connected as possible. She brought her legs around the back of his thighs, using them to pull him closer.

"Let go, Castle. Come for me. Come inside me." He slowed down long enough to kiss her languidly, before lowering his head to her ear. Kate was amazed…for all his exuberance in every other moment of his life, he was almost silent when he came, whispering her name in supplication with his release. He thrust twice more, filling her up, then kissed her shoulder before shifting himself off of her. They relaxed side by side, until he finally broke the silence with a question.

"So, are all of the dominoes down?"

She reached down to squeeze his hand. "No, Castle. I think they've only begun to fall."