This was inspired by a post on Tumblr earlier this week captioned 'Letters to Kate.' A few people suggested turning the idea into a fic so, well, here you have it. All credit for this idea goes to katiic. Also, many thanks to Beetlebug for looking this over and convincing me that it was good enough to post!

Assume an established relationship.

Disclaimer: [Insert witty comment about how I lay no claim to Castle and its characters]

SPIRAL BOUND

Flowers For Your Grave

April 2014

"Hey, Castle?"

"Yeah?"

He poked his head around the door frame, clad only in boxers and a t-shirt, toothbrush hanging out of his mouth. Kate stood in the office, bare feet curling against the cold wood of the floor, her hands tightly clenched around a smallish, rectangular object. Her hair was down, falling around her face in loose waves, a stark contrast to the tense lines of her jaw.

Whatever she was holding, he very much disliked what it was doing to her stress levels.

It took a moment for everything to register but when it did, Castle's first instinct was to panic. And choke on his toothpaste.

He hadn't hidden the notebook, per se, but he also hadn't planned on her finding it. Though given that he'd been digging through her desk at the precinct for years, it seemed only fair that she do the same to him here at the loft.

"Kate," he held out his hand to stop her, hurried back to the bathroom to finish brushing his teeth.

When he re-emerged, she was still standing by his desk chair, seemingly frozen in place. In her hand was his journal, a spiral notebook with a lightly textured black and brown leather cover. It was open to the first page, and her eyes were glued to the words hastily scrawled across the top two lines. The date in the upper right corner indicated that this – the first page, at least - had been written five years ago. Back when they first met. And the second line simply said "Kate."

"What is this?" she asked softly but shakily, lifting her eyes to his as he approached. Castle made his way towards her slowly, tentative, attempting to remain calm, but she could see in his eyes that he was unsure, maybe a bit apprehensive.

He came to a stop next to her, rested a hand on her hip. "It's... I write?" he offered sheepishly. "It's kind of my thing."

"This is from our first case. You barely knew me."

He shrugged lightly. "I know."

She turned her head, looked up at him. "So, why?"

"Have you read it?"

"No," she admitted softly. "I stopped when I saw my name."

He slid the book from her hands, closed it but didn't put it away.

"Castle?"

Silently he tugged on her arm with his free hand, guided her into their room, onto their bed. Only once they were situated, Kate between his legs, her back against his chest, did he hand the notebook back to her.

"I've been writing to you ever since that first case," he said softly, his breath washing over her neck, her ear, making her shiver and burrow further into him. "You can read it – all of it – if you want to."

"Since the first case?" she asked in awe.

Castle nodded against her, the day's worth of stubble scratching lightly against her skin.

"Why?"

"Because I couldn't just tell you. Talking wasn't really our thing."

Kate couldn't help but chuckle at that.

Her eyes dipped to the journal again and she flipped it open to the first page once more, faltered. "Are you sure?"

"I wrote them for you, Kate," he promised. "I mean, I never thought you'd actually read them."

"But... we should right?" she questioned, knowing that within these pages was their history. All the miscommunications and near misses and poorly timed confessions they'd never talked about. All the things they were simply content to ignore. All the things that probably needed to be brought out into the open.

Castle wrapped his hands around hers on the edges of the journal. "This is yours now. Ours. Just... you need to understand, some of this won't be easy to read."

Kate exhaled falteringly. She could do this. She really could. "Okay. I can handle it."

His hands left hers, came to rest on her biceps, squeezing gently. "You sure?"

She nodded, hesitating only slightly. "Just don't go anywhere, okay?"

Castle pressed his lips to her hair in response, wrapped his arms all the way around her. She took a deep breath, dropped her eyes once more to the first page.

Kate,

I don't really know why I'm writing this. I guess it's because if I said these words to you in person, you'd probably maim me in some horribly painful way. I'm rather fond of my anatomy and, given the choice, I'd rather keep everything intact. Besides, words are kind of my specialty.

I never thought I'd say this about any woman, but I'm glad you turned me down yesterday. If you'd said yes, we would have had our fun and that probably would have been it. I have no doubt it would have been fantastic. But then I probably would have woken alone in bed this morning, and I'd never see you again.

I don't want this to be the end, Kate. I don't say this about many people, but there's something about you that intrigues me, makes me want to know more. I know you have a story, much deeper and more complicated than the one I profiled for you yesterday. Maybe this makes me nosy, but I can't help myself. I'm a writer. I live for the story. And I want to learn yours.

I can almost guarantee you're going to hate me for what I'm planning to do later this afternoon. I know you probably don't want to see me anywhere near the Twelfth Precinct ever again. But yesterday when I went home, I did something I haven't done in ages; I wrote. I've been blocked for months, but all of the sudden there was a fresh new character in my head.

You inspired her, Kate. You're tough and strong (and sexy as hell) and I need more of that. I need to see you in action, get to know you better. I want to learn about what drives you, what makes you so good at your job.

So please don't hate me for showing up at the precinct in a few minutes. Like I told you during the case, I'm here for the story. And now I'm here for your story, too. For research for my next novel, starring a smart, savvy female detective. I promise, you're going to love her!

I know you'll never read this letter, but it feels so much better to have this all written down. I guess you could say it helps me organize my thoughts, sort out my feelings.

And if you do end up hurting me for barging into your life this afternoon, well, perhaps someone will stumble across this and they'll know the reason behind my demise.

I'll see you at the Twelfth in a few minutes.

Please don't shoot me.

-RC

Silence filled the room as Kate finished the letter, tried to decide what to say. She didn't let go of the journal, but loosened her grip, allowing it to rest against her thighs.

"You were glad I turned you down?" she asked eventually, doubtfully.

"Yes. I was." He squeezed her tighter, planted a kiss on the side of her neck. "Though not nearly as much so then as I am now."

"Why?"

"Because if you hadn't, we probably wouldn't be sitting here."

Kate allowed a small smile to escape briefly before returning to the list of questions floating through her head.

"You still wanted to sleep with me though." Actually, that one wasn't really a question.

Castle chuckled, the vibrations flowing through his body, still pressed tightly against hers. She could feel the contraction of his abdominal muscles against her back, shivered as it rippled through her.

"Of course I did. You're hot as hell, Kate. What man wouldn't want to?" He trailed his fingers down to her waist, his large hands nearly spanning the slim distance, emphasizing his point. "I won't lie and say I wanted more at first because we both know I didn't. But the moment you sauntered away from me, it became a challenge. I still wanted you, but for the first time ever, I was going to have to fight for it. I'd never had to do that before, and that, truthfully, is what drew me in."

"I... really?"

"You know how stubborn I can be," he smirked proudly.

Kate turned her head, pressed her lips to his cheek once, twice.

She felt him smile against her as she spoke again.

"I'm glad you stayed, Castle."