A/N: This is based on an observation I had when I watched Probable Cause, specifically the scene where Beckett watches Castle being taken away by the officers at the elevator. This is set somewhere in Season 5 between the Christmas and Valentine's Day episode, assuming Andrew Marlow hasn't cheated us out of hearing Beckett's first "I love you" by letting it happen of-screen.

"I'm sorry", Castle looked up at her apologetically. It was Beckett's day off and usually they spent it together doing couple-y things, but he'd woken up at five in the morning, kissed by the muse, and snuck to his laptop in his office. That's where she found him, when she got up a few hours later.

"No need to apologize, Castle", Beckett shook her head, "you're obviously on a run, better take advantage of it." Kate leaned against his desk, barefoot and clad only in his shirt from yesterday. She ran her fingers softly through his hair.

"But", he opened his mouth to protest, when she leaned forward and shushed him by putting her fingers on his lips.

"No buts. We don't always need to plan something special on my day off."

"But I only get you to myself for a whole day once a week and I don't want to spend it away from you writing." He mumbled against her fingers, stealing a kiss against her fingertips.

"Then don't," Kate shrugged.

Castle frowned.

"Just because you're writing doesn't mean I have to leave, do I?" She looked at him insecure.

"No, no. Stay!" He assured her eagerly.

"Good, so I'll grab a book and read in your office while you write," she suggested, "unless you'd find that too distracting?"

Castle grinned and grabbed her hands pulling her down onto his lap. "Sounds perfect", he kissed her soundly. "I'll make it up to you tonight."

0~0~0~0~0

They ended up on the couch in the living room after breakfast. Castle propped his feet on the coffee table, carefully balancing his laptop. Beckett was stretched out lazily, her head resting against her lover's thigh.

"You're really not mad at me?" He looked at her skeptically.

Kate rolled her eyes, "Jesus, Castle, how many times do I have to tell you until you believe me?"

"So it's just a co-incidence then that you're reading the latest Patterson?"

Kate snorted and shut her book with a loud thud. She'd snatched Castle's advance copy from his office. She dipped her head back slightly to get a better look at him, "It was lying on your desk and it's not like you've come out with something new lately."

"Ouch! You wound me," Castle touched his heart in mock hurt. "And whose fault is that?"

"Are you saying I'm keeping you from writing?" Beckett shot back, giving him an incredulous look.

"Nope, I'm saying I love spending time together with you more than behind my laptop."

"Well," Kate dipped her head back down, "now you get to have both."

"I like it", Castle admitted. She didn't need to turn back around to see his smile; she could hear it in his voice.

"Me too", Kate smiled into her book.

"It feels nice. Domestic."

"Castle?"

"Yeah?"

"Less talking, more typing. I do have plans for us for later."

0~0~0~0~0

The afternoon found them in switched positions, after Beckett made them a late but light lunch. Kate was the one sitting on the couch with her feet propped up on the coffee table and Castle was the one lying with his head in her lap.

"Are you sure you're comfortable?" Beckett glanced at him.

"Totally", he replied without looking up from his screen, his fingers flying across the keyboard.

"You don't look comfortable", Kate said and shook her head. His feet were outstretched but elevated on the armrest and his laptop propped upright somewhere between his crotch and belly. She had honestly no idea how he did that. It must hurt though she was convinced.

Castle rolled his head back, giving her his boyish smile, "Nah, I write like this all the time. Staying too long in one position is way more uncomfortable."

"If you say so", she replied clearly in disbelief.

"Promise", he winked at her and then shuffled a bit around, until his head and shoulders rested comfortably on her. "Now stop trying to sneak a peek at Hampton Heat. Huh! That rhymes!"

Beckett grinned and looked for the bookmark, eager to read the next chapter.

"Maybe I should try my hand at Nikki Heat erotic crime poetry?" He peered up at her.

"In your dreams", Beckett snorted.

"What? You think I'm no good as a poet?"

"Your rhyming puns are awful, Castle, and corny half the time. Nobody wants to read erotica written by Dr. Seuss on crack." She shuddered.

"Alright, alright, I'm sticking to prose." Castle grumbled, giving in reluctantly, "Might still try my hand at a private, intimate poetry reading tonight."

"Sure", Beckett humored him, "go ahead and I'll cancel my plans for us tonight."

"Fine." He pouted. "Just so you know, you're no fun today."

Kate laughed out loud, shaking her head.

"Just write, Castle, ok? Get it out of your system so I can get you back into mine." She sighed.

"That line is so going into the next encounter between Rook and Heat." He practically drooled and Beckett rolled her eyes.

0~0~0~0~0

A few hours later, Beckett glanced down at Castle who was furiously typing, mumbling barely intelligible syllables. He was completely caught up in the world of Nikki Heat and whatever he'd planned for her and Rook on their vacation in the Hamptons. Kate sighed heavily thinking about how terribly awry their first secret romantic getaway had gone. She'd had it all planned out. She thought she'd tell him in the Hamptons.

He'd already said them. Those three little words. Twice. In the heat of the moment, pleading with her for her life. Both times. The first time she'd been in no condition to return them, considering she'd just passed out from the blood loss caused by her bullet wound. And the second time, well… She'd been so angry with him; his words hadn't truly sunk in until she'd sat on the swings in the rain. A whole year he'd waited for her to come to him. Let it happen on her terms. A whole year he'd loved her secretly from a distance, no matter how many times she'd pushed him away, he still loved her. She hadn't been ready yet that night to say them back. And he didn't push. Probably just glad she'd finally chosen him over her mother's killer. Traded her past for the present; perhaps even a future with him.

He hadn't said them since that heated exchange in her apartment half a year ago. She didn't mind, really, because he'd said them after all, and meant them, of that she was sure, but somehow she'd felt a bit cheated. It should have been romantic. It should have been a special moment…. but not as special as a frantic deathbed confession under the duress of a shooting. Not something thrown out there carelessly in an argument. But she understood, he'd been at his wit's end, and she'd pushed his buttons and it slipped out.

And so, when she was ready, she decided that her first "I love you" had to be something special. Romantic. And big, for Castle's sake, cause he loved big and romantic. And this was really more for him than about her, wasn't it? And under no circumstances whatsoever it should and could be linked to near death experiences, exploding apartments, government assassins or any dead bodies of any kind. And tigers. Period. It had to be one of those moments they'd always remember fondly, unlike their break up fight or her attempted assassination. Something untainted by their lives as a homicide detective and mystery writer. Something to cherish forever. And so she'd forged the perfect plan to tell him she loved him under the stars in the Hamptons. That should satisfy both their romantic streaks. They couldn't find a more peaceful place away from all the murder and mayhem in the city than Castle's beach house in the Hamptons.

They'd start out with a romantic dinner at a restaurant with a view of the ocean. They'd take a walk along the beach back to his house under the moonlit sky. She'd slow down, tug on his hand a little bit until he'd stop and turn around. He'd look at her curiously, speculating with sweeping her off her feet and walking her into the ice-cold water, teasing her, until he'd see the sincerity and seriousness in her eyes. He'd take a step towards her instead, intertwining their fingers, pulling her to him. She'd let him reel her in until their chests were flush against each other. Her hand would come to rest on his shoulder, slowly trace down the pattern of his shirt, feeling the pectorals of his chest underneath. She'd smile at him, and he'd smile back. She'd lean in, for a slow and gentle kiss, slipping him a little tongue as a token for later. She'd pull back first, he'd still have his eyes closed. She'd run her hand through his hair – she was slowly but surely getting addicted to that – watch his eyes open slowly, and then she'd lean in again and whisper those three little words softly against his lips before she'd close her mouth around them again.

And then stupid Randolph Franklin had to stumble into his yard and take the romance out of their secret romantic getaway weekend with a big fat splash into Castle's pool. And on their first fucking night no less. They'd been so grossed out, they hadn't even swum once in it, and Castle had been subsequently begging her to take another weekend off to cash in that rain check on the skinny-dipping. It hadn't helped that Castle became obsessed with solving the murder, either, and the whole mood of the trip changed to secret work weekend.

Then the whole Jerry Tyson mess happened. She'd almost told him, when she'd cuffed him. The words were already on her lips, this might be the last time she'd ever see him alive. And she wanted him to know, needed him to know that she loved him with all her heart. That he was her one and done. But she couldn't. She needed him strong, and fighting. If she told him now she loved him, he'd think she'd given up. It would feel as if she was going to say good-bye to him forever. As if she knew she was never seeing him again. And she couldn't risk him giving up. She needed to give him hope, keep him believing that she was gonna do everything in her power to get him out. Losing him was simply not an option. And so she just told him that as she laid the handcuffs on him.

Beckett wasn't gonna cry, as she walked him through the precinct, feeling the eyes of everyone on them. Javier's and Ryan's sympathetic looks, curious glances from uniforms. She walked a step behind him, her hand resting on his back. To everyone it looked as if she was just making sure she'd be able to tackle him down if he attempted to flee. They knew better. She couldn't let go of him, not if this was the last moment they'd be together. She wanted him to know that she was there for him in his hour of need, that she'd walk beside him with her head up high, knowing he hadn't done anything wrong, even if the others in the precinct still had their doubts. She wasn't going to abandon him and most of all, she prayed that the small gesture of her hand on his back would give him the little bit of extra strength he'd need to survive the tombs.

Kate withdrew her hand and put some space between them, when she saw Gates and the officers waiting at the elevator. She had to. It was too painful. All she wanted to do was hug him and tell him she loved him and that everything would be ok. Gates be dammed. She was so scared but she couldn't let him see that. He had to believe in her, she couldn't afford to show any weakness now. How many times had he come to her rescue and saved her life? Now it was her turn. And so she watched him enter the elevator. Looked into his eyes one final time, the words back on her lips. She could mouth them to him, he'd understand. Her lips opened and formed an 'I' before she closed them again helplessly, the other words stuck in her throat.

She almost told him again on the way back from the warehouse to the precinct, so they could officially process him out. The imminent danger over, he sat in the car, alive, right next to her, and she just wanted him to know. That's when Tyson crashed his car into hers. When it was all over, Castle was still brooding for days over Tyson's possible escape. She'd find a better moment to tell him. For now her touch had to be enough to take his mind off of things.

Before they knew it, the holiday season had caught up with them and as much as Kate was dying to tell him she loved him, their first Thanksgiving and Christmas together put already enough pressure on their relationship, she wasn't sure she could deal with the emotional aftermath of exchanging their first 'I love yous' on top of that. As expected, Castle had gone overboard with the celebrations of both holidays, completely overwhelming her with his holiday spirits. When she'd walked into his apartment on Christmas Eve, her first thought was that Christmas had thrown up all over his loft. It was as if he tried to make the holidays so spectacular she wouldn't get a chance to miss her mother, which made it only worse. Christmas movie marathon, gift-unwrapping orgy, and ice-skating at the Rockefeller with Alexis, a Christmas gala performance of Dickens' A Christmas Carol with Martha – he'd thought of everything – a nightly role-play of naughty Santa included. And all of a sudden Beckett felt suffocated and was convinced if she told him she loved him it would be her death sentence. It took all she had to stay, always ogling his front door for the quickest escape route, trying so hard to be a part of his holiday traditions all the while thinking about her father alone in his cabin upstate.

Kate was determined she'd tell him before Valentine's Day because really that would be too cliché. She did not want her first Valentine to him be a love confession. That was just cheesy and no. Just no. That left Beckett with exactly five weeks to plan the perfect moment to tell him. She still wanted it to be romantic. And intimate. She thought about big because Castle obviously loved big, but… Definitely not in a public place like a restaurant. Maybe a walk in Central Park? Maybe her apartment. With the right set-up, it could be big and intimate. Beckett grinned. She could create a sea of rose petals and candles in her bedroom so Castle could get in touch with his inner girl.

Soon another plan had begun to form in her mind one night, when Castle lit the fireplace and threw down two pillows for them to lounge on. Kate watched curiously as he puttered around in his kitchen, until he found what he'd been searching for. He returned with two glasses of red wine and a pack of marshmallows. Beckett grinned and Castle beamed at her, looking truly like a nine-year-old on a sugar rush. He handed her her glass and an iron poke, then joined her on the floor. They'd spent the rest of the evening roasting marshmallows and making out in front of the fireplace. And if Martha hadn't come home early, they'd have probably had sex there too.

Beckett smiled at the memory. Ever since that night she'd been waiting for the perfect moment to repeat it. They'd have the loft all to themselves. They'd light up the fireplace after dinner and cuddle up in front of it. He'd start to feel her up, playing with the buttons on her blouse, until he was satisfied with the amount of cleavage she showed. He'd trail soft kisses from her neck to her shoulder, trying to sneak in a hickey, just because he thought it was funny and some primal part of him liked marking her for other men to see. She'd slap him softly, cupping his chin and leading his mouth back to her lips. He'd give her his boyish smile, the one he'd used all those years to weasel himself into her heart and the one that melted her heart, when he used it on her now.

They'd watch the flames licking the brick walls of the fireplace, reaching higher and higher, mirroring the fire burning inside them, threatening to consume them. He'd try to take off her clothes, but she'd swat his hands away. He'd start to whine and complain and she'd shush him with her fingers on his lips. She'd straddle him and kiss him long and hard. Driving him crazy until she'd be able to feel him squirm underneath her. She'd reduce him into a quivering mess just by using her hands and lips. And then she'd go in for the kill with her words. She'd stop waiting for him to regain his senses, for him to open his eyes at her until he looked at her with those beautiful blue eyes, full of love and desire. She'd lean forward to nibble on his earlobe and then turn and whisper into his ear how much she loved him. Then she'd switch sides and do the same to his other ear and she'd whisper to him how much she needed him. She'd return to his lips, kiss them softly, telling him how happy he made her. Provided he hadn't flipped them yet and she wasn't on her back on the floor by then, watching him hastily pull off their clothes, so he could make love to her.

And then there were of course those moments when she held them back on purpose. Those three little words. To punish him for letting Meredith stay at the loft and putting her into an impossible situation. Beckett still couldn't believe he'd actually put her on the spot like that, asking her in front of all the others whether she was ok with it? She could practically see Martha and Alexis face palm mentally, staring incredulously at Castle. He could be so clueless sometimes. How he put together clues in his crime novels was beyond her.

It may have been a bit childish but Kate felt he didn't deserve to hear those three little words from her then. Or when he made fun of her for liking Nebula 9. She didn't mind so much at first, after all she'd done her fair share of teasing him about his stuff, but he must have noticed after a while that Nebula 9 was more than a guilty pleasure for her. And he kept ridiculing it right until she'd given him the little speech about Lieutenant Chloe. Then he'd let it go, of course, as he always did once he found out how meaningful things were. Like her Christmas tradition. She wasn't sure what unnerved her more that he didn't always quite catch on right away how meaningful some things are or that he immediately let them go once he found out about the back-story. She shouldn't have to tell him the back-story, by now he should just know when to back off or ask for it straight away, without the teasing and pouting.

It wasn't until the aftermath of their meet-the-parents dinner that she realized she's been waiting the whole time for the other shoe to drop. They'd created this cocoon of love around them, as if it would protect them from the real world. And she was so incredibly in love with him, she wasn't sure she'd been this crazy about another man before. She really wanted this to work. She had meant it when she told Castle she was just waiting for the right person to just delve into it. She thought that's what they'd been doing, but then she realized she was still dancing on the cliff staring into the abyss, afraid of taking the leap. Because what if Castle let go of her hand mid-jump? She wasn't sure she wanted to do this without him. She certainly didn't want to do this with someone else.

So Kate stayed in their bubble, holding back with her declarations of love afraid they'd prick their bubble and cause it to explode. She refrained from making rash decisions, she'd been adamant they take their time and things slow. As if the sharp blade of moving in together would create a rift in their bubble. Because as long as they were in their bubble it was just them.

But what if they left their bubble and he suddenly realized she wasn't who he'd thought she was? What if chasing after her for four years had left him breathless and unwilling to run to the end of the world with her and back? What if Castle found out all those annoying things about her that had turned other men off before in her life? What if he'd created this idealized version of her in Nikki Heat that she had no possible way of living up to? What if he found all the things she liked in life ridiculous like her Nebula 9 obsession?

Would he be able to look past the negativity of all those things and still come home to her? When he realized she didn't do her laundry until she did not have a single shred of clean clothing left she could wear? When he found out that she forgot to clean the shower drain of her long hairs half the time? What when the excitement of sex every night wore off and daily routine set in? Would he still love her when she took him grocery shopping in sweatpants? When she traded his arms for a long, relaxing bath and her favorite book after a hard and long day at the precinct? What would he do when she rejected him for the first time because she had cramps and hot flashes and a carton of rocky road sounded and looked and felt a thousand times more appealing than him crowding her because he wants to help?

What would she do when he was practically bouncing off the walls, full of energy, and begging her for a game of laser tag, when just the thought of getting up from the couch seemed like an impossible feat? How would he react the first time she turned him down, when he offered to pay because she started to feel like a kept woman? And really, it was just a question of time until the bubble burst. They always did. No relationship can stay in the romantic bliss of the early months. Once the bubble burst, they'd never retain that feeling of being completely enraptured in each other's love.

She glanced over at Castle who was still typing away on his story. She smiled wistfully and ran her fingers through his hair. He threw his head back and peered up at her with the brightest smile. And then it struck her. Feels very domestic, he'd said earlier. And he was right. There she was in his loft with his head on her lap, the poster couple for domesticity. And it felt so very nice, so natural. She'd meant it when she'd said earlier they didn't always have to go out and do things as a couple on her day off. The way he'd smiled at her just now, content and happy just to be there with her told her everything she needed to know. He wasn't going anywhere. Just like she wasn't. Because this is what they both wanted. Being together, sharing their lives. It didn't matter what they did as long as they did it together. No words were needed between them. They just were. Period. Rick and Kate. Or Kate and Rick. Or Caskett as he'd referred to them back in the Hamptons. This was reality. And it no longer mattered if or when the bubble burst because, truly, reality had started to seep into their bubble long ago. And now they just had to make it work.

This was it. Sometime today they'd left the early stage of their relationship behind and hadn't even noticed. If this was what reality felt like, she could deal with that. Even get used to it. They'd now entered the stage where the freshness of the relationship would begin to wear off and the domesticity would settle in. And it felt sooooo nice. They would have all the big discussions about moving in together officially, consolidating properties, finances, marriage, family, and sometime in between they should probably come out to Gates. But first, first there was something she had to do that was long overdue. Because, really, this was perfect. Him writing and her reading on her day off just enjoying each other's company quietly was as perfect as it could get.

0~0~0~0~0

"You've stopped typing", Kate noted and broke the comfortable silence of his loft. "You done?"

"Yeah", he nodded as he closed his laptop, "think so". Castle rolled his head back to look at her.

"Good", Kate replied as her lips descended onto his in a quick kiss. She couldn't hold the position too long, quickly feeling all kinds of bones and muscles in her back protesting at the awkward angle. She reached for his laptop and lifted it from his lap, when she straightened up again.

"You're not reading anymore", Castle stated matter-of-factly.

"Nope", Backett smiled and placed the notebook on the coffee table next to her book.

"Oh yeah?" Castle pulled himself more upright resting his back against her legs now and reaching with his left arm across her lap to prop himself up. "Been watching me work like the creep that you are." He grinned.

"Figured I'd give you a taste of your own medicine." Kate shrugged, enjoying their light banter. Castle leaned forward and captured her mouth with a slow and long kiss.

"Mmm, best tasting medicine ever", he declared once they came up for air. She played with the hem of his t-shirt, twisting the fabric between her fingers.

"Kate?" He gazed at her, concerned. He hadn't missed the serious look in her eyes. Something was up.

"Hm?"

"Something wrong?"

"No", she smiled at him reassuringly.

He raised his eyebrows.

"Really, Rick, I'm fine." She sighed and closed her eyes, still smiling, "perfect actually."

"So about those plans you mentioned earlier, do they involve your handcuffs?" He traced invisible patterns on her arms.

"Nope", Kate lifted her arms to stroke his in return. He was only wearing a T-shirt and so she could freely roam the skin of his arms. "But I think you're gonna like it."

"Oh yeah?"

"Mhm", she continued, biting her lower lip, "There's something, I've been dying to do for quite a while now…" she trailed off.

"Okay", he drew out the word. Did Kate Beckett just flash him a coy smile?! "Are you sure it doesn't involve your handcuffs?"

She nodded. She didn't roll his eyes at him exasperated as he expected. Something inside him tensed, he didn't know why but the air in his loft suddenly felt charged.

"So…" he looked at her curiously, "nothing kinky then?"

Kate shook her head and laughed lightly. "Afraid not" Her fingers wandered up his biceps to his shoulders. "It's just something I've really wanted to do but didn't know how?"

She looked at him and he raised his eyebrow expectantly and curiously.

"I've been waiting for the right time, but the moment seemed never right. And I wanted it to be perfect because really you deserve nothing less. And then I realized there are no perfect moments, just the right time. And I know how you like big…" she trailed off.

And suddenly he realized what this was about. His pulse picked up as his heart started beating just a little faster. It was stupid really. He knew she loved him, he could see it in the way she looked at him, feel it in the way she touched him, hear it in the way she called his name. And yet… He'd been waiting so long to hear those words from her. More than once he'd bit his tongue, when he was ready to blurt out his love for her. Again. She knew by now how much he loved her and he didn't want the first time she said it to be an automatic reply to his repeated professions of love. He grinned. This was huge. This was it.

She watched him carefully; she'd noticed his change in demeanor. She knew he knew. If possible her smile got even broader, quite possibly matching his own. Her eyes started to spark a little bit more if at all possible.

"… but big isn't me and while I'm not ready yet to shout it from the rooftops for all the world to hear…"

Castle opened his mouth to tell her she didn't have to say it if she wasn't ready. She didn't have to justify herself. But her fingers caught his lips and she ran her fingertips softly along his lower lip. And then he felt her palm flat against his cheek, her thumb gently caressing his skin. And oh the look in her eyes, pure love for him.

I love you. No. Richard, I love you. I love you, Rick. She tried out different versions as she held his cheek. Funny, she'd never actually thought about what she'd tell him exactly. She watched him close his eyes and nestle into her touch. Turning his head slightly until his lips could reach her palm and kiss its skin softly. Her other hand went to his head, her fingers sifting through his thick hair. His eyes snapped open and he turned to look at her as she leaned in closer. And suddenly the words came out so naturally before her mind could filter them.

"I love you, Castle, you're my one and done", she whispered just loud enough for them to hear before her lips descended on his in a searing kiss. His smile widened and his eyes lit up with his own love for her.