Title: One Thing

Author: eyrianone

Rating: K

Spoilers: Post-Ep 'Watershed'

Summary: But he looks terrified down there on his knees with no joy in his eyes and no smile on his face. . .

Disclaimer: (From ViaLethe) – 'Words are mine. World ain't.'

A/N: 'Unfinished' is waiting on an update - I know, but sometimes you have to get something else out of your head first, especially when a string of episodes (the last three) completely throws you for a loop.

You're always hoping that we make it
You always want to keep my gaze
Well you're the only one I see
And that's the one thing that won't change

Lyric from 'Never Stop' by Safetysuit

She's bracing for the blow, for the moment when he breaks it off – breaks her heart – so when Castle slips from the swing seat and finally looks her in the eyes while he's on his knee with a ring in his hand – Kate freezes.

She goes completely still inside, and the only thought in her head is, 'not like this'.

Not when he's mad at her – and rightfully so.

Not when there's been distance between them recently, misunderstandings and miscommunications, and the shadow of Eric Vaughn in his eyes sometimes when he speaks to her.

Not like this, Castle. Not today.

Three seconds ago she was certain, completely certain that he didn't want her and that her deceit, her inability to lower the last of her walls had finally pushed this man she adores away. She'd known absolutely that she'd lost him, so it's just too overwhelming in the moment that nothing – nothing could be further from the case.

God, he wants to marry her. No conditions, no ultimatum, just the pure truth of his love for her on display in this simple, meaningful setting. But he looks terrified down there on his knees with no joy in his eyes and no smile on his face, and as his eyes cloud over and he looks down Kate realizes it must be both shock and horror that are visible on her face, and he thinks, oh he thinks . . .

She moves quickly then. Slipping from her own swing seat she kneels on the grass before him, before she practically throws herself into his arms.

"Ask me again," she pleads against his ear, her lips brushing against the sensitive shell and she feels him shiver where she holds him so tight, so closely against her.

"Kate . . ."

"Not today," she says swiftly, "Not today, Castle. Not like this, not when there's so much we need to say."

"Kate, please-"

"I love you." She crushes him ever more tightly. "I love you, Rick and I want nothing more than what you're offering me, but we need to earn that. I need to earn that and I want joy in your eyes, happiness in your smile when you give me that Castle. So please, please just wait – and ask me again."

He pushes back out of her arms and his face is clouded with uncertainty, the fingers of his left hand bite into her shoulder.

"I want you to say yes," the words spill out of his mouth.

She nods, "I want to say 'yes' too. I do. God, Castle – but I thought you were about to break up with me. I thought this was the end." Tears fill Kate's eyes and she blinks them back, adrenaline is coursing through her system now, as is relief, just an insane almost giddy relief because he's still hers. Because they're still 'them'.

The clouds in her partner's eyes disperse immediately.

"No, no, never. 'Always', Kate – I mean it," his tone is fierce, proprietary.

He makes to pull her into his arms again but he winces suddenly, the pressure on his still recovering kneecap suddenly too much.

Kate scrambles to her feet and then tugs him up, her eyes dropping once more to the simply stunning diamond ring still clutched in Castle's right hand. She believes, firmly believes this is the wrong time for this – but there is a huge part of her that just wants it so badly.

"I'm glad you like it." His soft whisper finally tears her eyes away and she stares up him, stunned and so happy to see the beginnings of a smile on his handsome face.

She feels the corners of her own mouth immediately curve in response.

"It's beautiful, Castle. And I want it – I just need you to keep it safe for me, just for a little while longer. Okay?"

He nods, and pockets the ring inside his jacket, before he takes a deep breath and wriggles the tension out of his broad shoulders. His face has gone serious again when he focuses back on her.

"You've made a decision though, haven't you?" he asks. "About the job offer I mean."

Kate bites her lip, she has.

"I'm not going to take it."

She waits for him to smile his relief but instead his serious, subdued demeanor stubbornly remains.

"Why? I'm not asking you to choose," he says firmly. "I'm in this; I'm with you – either way. Kate, you'd be amazing at it, you must know this. The Feds know it, that's why they want you. And I'll get over missing being a part of what you do, I swear I will, after all I can write – anywhere. If I can be your partner in life, that's all I need."

She kisses him then, the love pouring out of her and into him, her thanks for his brave and unselfish heart. What he's done today – she knows how hard, how truly terrifying it must have been for him. To open himself up, lay himself bare, risk the rejection – only he could have done it and she's so grateful, so damn grateful for him and the way he understands her.

"I know you're not," she breathes across his lips when she can tear her own away.

"So if you . . . if you did make this choice, I mean . . . "

"I made it for me," she states quickly when he trails off. "And continuing to be your partner, Rick - was most definitely a part of it, but it wasn't the biggest reason. Castle, I just realized that my heart is here."

"What-"

"You and me, Esposito, Ryan, hell even Gates – we're a family. What I do, what we do everyday makes a difference and I've always been proud of that. I might have allowed it to consume me, to be my life for too long but since we've been together Castle – oh my life has become so very much more. I'm living – I'm really living – finally, and this federal job would completely change that. It would require parts of me that I've realized I'm just not willing to sacrifice for anything ever again – not now. Not when I worked so hard to be more for the future that I already have here. The Twelfth is my home, the relationships that I value are here. Even the someday, maybe, hopefully, family that I want – with you, Castle – it's all here, including the job that I'm meant to do."

He still looks pensive.

"Are you sure that you won't regret it. Kate, I couldn't bear . . . "

"This is my decision. No regrets." Her voice is clear and determined, her stance is firm, sure, and yet he can't get past his need to say this,

"You just seemed so certain, when we fought, Kate. I know at that point you believed that you wanted it, and I'm not meaning to question – in fact I can't believe I'm still questioning this . . ." his lips quirk into rare, wry smile.

"I did – want it I mean."

"So, what's changed?" he asks carefully.

"Me," she says it confidently – boldly. "I've changed. This job appeals to who I was before you, Castle. To who I was before 'us'. And I slipped back into old patterns there for a while, I'm truly sorry but I did. I started to question internally, I started to doubt things and this offer was like kerosene, it gave my doubts all this fuel, gave me an easy, familiar escape."

The writer takes a shaky breath, "Doubt things? You mean me."

There's pain in his eyes again when he says it. A cold, stark fear just sitting there visible and though she wants to, Kate won't let herself look away. They've got to talk this out now, got to leave any questioning of their commitment level behind them.

"We never talked about where we're going," she blurts out. "And it took me until today to realize that's because you've been relying on me to lead, Castle. Haven't you? You've always pushed us forwards and I just didn't see until today that you'd stopped doing that for us. That what was actually happening wasn't you losing interest or us getting stale, it was you trying to go at what you thought was my pace."

Her partner sighs, "You thought that? I mean really? Kate, I didn't want to scare you off, and if we're being honest here – I was scared too. Things were so good, so very, very good. I kept telling myself that if I did nothing to rock the boat things would stay good. Pushing you for more – it seemed like an unnecessary risk to take. It never meant I didn't want it – I want all of it with you. Every piece, every moment I can get. I've never been good at commitment until I met you because I never wanted it badly enough – but you, Kate being with you is everything."

She reaches for his hand, slips her slight fingers between his and rejoices when the broad warmth of them curls around her.

"You know we've always been risk takers, both separately and together, Castle."

Something sparks in his eyes finally and the writer tugs her hand up to his mouth, brushes his lips softly over her fingertips and heat curls insistent and immediate Kate's belly.

His reply is low,

"Yeah, we have. I'm sorry Kate, I never meant for that lack of push to make you doubt me."

Looking into the earnest regret that lines his mouth Kate believes him; and it pushes her to tackle what she knows still hurts him.

"I've given you plenty of reasons to doubt me too, Castle. What happened with Eric Vaughn . . ."

"Kate-"Her partner's eyes close and his face contorts a little in distress – slight but enough to let Kate know that she's correct in believing the incident still wounds him. As she watches, he sighs quietly then schools his expression carefully before he looks back at her again.

"You don't have . . ." he starts.

But she stills any further protest with her fingers firmly over his lips.

"I do, no more 'not talking' through things okay? We'd gotten so much better at it and then with Vaughn we started to slip back," she says. "The truth is that he said things that flattered me, Castle. He told me I was special and made me feel like he knew me, and he's Eric Vaughn – I'll admit I was enamored and a little in awe of him. All he wanted was to sleep with me and he used his money and his influence in order to achieve that aim. And even once he knew I was in a relationship he didn't back off, and that's classless - sleazy. I can't actually believe I didn't see that at the time. It was never your fault Rick, but my ego was bruised and so I let things with Vaughn get way too far. He should never have gotten that close, but I swear to you I would never betray you. You have to believe that Castle, and if it takes a while I will earn back your trust. I got mad at your jealous behaviour and then promptly handed you a reason for it – it was very wrong of me."

He holds her gaze and then puckers up his lips to kiss her fingers still over his mouth; raising his hand he gently pries them away.

"It did hurt, Kate. I'm not going to lie. But I believe you."

She nods.

"Still, I gave you cause to doubt me, and then with hiding this job offer I gave you cause to doubt me again, and yet I really want you to believe that nothing and no-one could ever lure me away. You know I chose a long time ago to become a cop, and today I realized that I chose it still. But you should know you come before any of that Castle, because when everything else is stripped away what was true a year ago is truer still today, in the end I just want you."

Smiling, Castle wraps her up in his arms and tugs her against his body. He buries his face in the crook of her shoulder and simply holds her there, sighing softly with pleasure when Kate tangles her fingers in his hair.

"I love you, so much," he whispers. "Whatever happens, you need to know how I feel will never change, Kate. Doesn't matter what comes I will never not want you."

She believes him, she does and it feels so very good. So though it might have been ill-timed his proposal has certainly given her this much now – a firm and mutually committed place to stand, so Kate takes a deep breath and gives it back to him.

"When the time is right and you ask me again, Rick – my answer is yes."