"Do You Have Any Idea What You Do Me?"

This is my first Castle fic. I am no stranger to writing in general, but I am very excited to explore these amazing characters on my own... That being said, I do not own nor am I affiliated with Castle, ABC, or Disney. I am just a loyal fan.

Summary: The walls continue to come down as Kate decides to take a leap in the first days of their relationship. I suppose this story could be considered a Finale-Fic, but there are no spoilers. Rated M for safety.

Props to those who pick up on The X-Files reference.

Castle was positioned over her, holding his chest and waist up so as not to crush her. He was between her legs, keeping physical contact between their most sensitive areas. The friction of his arousal through his boxers against her was maddening. So close, but that thin piece of silk was enough to frustrate her. She wanted their skin to collide, all of it. She wanted it all tonight. Fast, slow, it really didn't matter. She knew there would be time to take things slow, to talk, and to learn all the nuances of each other's bodies and hearts. There would be time to get to know each other on these new terms. Tonight felt like a reckoning, his face like a beacon light, and she just needed it, needed him.

As he kissed her neck, he buried his face into the space that seemed to fit him so well, like a puzzle piece. She wrapped her arms under his and over his back, stroking him all over that large expanse of him. The way he moved made her whimper his name in a way that brought about a smile against her flesh. She could feel it. Her voice, his name motivated him further as he ran his hands through her hair, gently grabbing as she pulled her head up to meet his lips. They kissed with a fervor that was new and desperate, but trusting and full of faith. The collective tension of years spent yearning was fuel for their lips and tongues, and she groaned with loss as he moved again back to her neck and throat. She lifted her head again, as if to chase his mouth, before collapsing as she felt his hands and mouth all over her.

"Castle…" she breathed heavily towards him, "Do you have any idea what you do to me?" she asked. She bit her lip and turned her head in response to the arousal that had been building for the last several minutes. Or was it years? Or seconds? It was hard to apply time to such an event, because it felt like they had been doing this forever.

It took a moment to notice the absence of his ministrations, and then she realized that he had stilled. She could feel his hands, one on her hip and the other on her torso, but instead of exploring, they were motionless. She could still feel his mouth on her neck, but instead of his tongue dancing over her flesh she felt his heavy breathing heating her skin.

Panicked and confused, she put her hand to the back of his head, and she felt him shudder. She thought back to words and moments blurred by passion and realized the weight of what she thought was a rhetorical question, something innocuous in no need of an answer. "Do you have any idea what you do to me?" she had asked.

She was shocked when she realized what the problem was. He had no idea. He had laid his cards on the table again and again, but she had yet to push past that declaration. It was no wonder he seemed afraid whenever she left the room, as if she would never come back. Richard Castle didn't know that she was always going to return to him now that they had found their way to each other. She was certain, but he didn't know, and she had to remedy that.

As Castle continued to breathe against her, static and without movement, thinking about the question that, to him, held so much weight, she moved her hands to the sides of his face and pulled him from the crook of her neck. His eyes were dark, and in the shadowy dusk of his bedroom, she could swear she saw tears in his eyes. Her heart twisted in her chest at the realization, and she felt selfish, ashamed, and desperately in love, all simultaneously. She put her forehead to his and looked into him as deep as she knew how, and spoke.

"Do you know…" she started asking before shaking her head. She thought it best just to tell him. She knew he needed to know, and she needed him to hear it. "Castle." She breathed, her lips leaned towards his as she spoke, "Castle, you… you are it." She emphasized the last word, and continued. "You are my constant. My touchstone. You keep me sane. You are everything."

She could feel a response in his hands as they began moving again, and she arched up as he touched her abdomen and her sides with careful, gentle fingers. His eyes were closed, and she wiped a single tear away from his eyes and bit her lip as she continued to hold his face in her hands.

"I want you… more than anything, Castle", she whispered, punctuating the words as best as she could. She felt his breath hitch in his throat and he moved to take her lips in his, affected in a million ways by her words. She held him at bay for a moment, smiling. "Hey, hey, Castle. I'm doing pretty good here so don't interrupt me", she said with a smile on her face and love in her voice. He smiled and ran his lips across the bottom of her chin.

"Castle, seriously. Just one second", she chuckled, moving her head from left to right to avoid his distracting lips. She slowed her movements again when his head fell back to her shoulder, and she moved her hand through his hair, resting on his upper back. "Look at me", she said, with only seriousness in her voice. He lifted his head to make eye contact with her again, and she stroked his cheek with the thumb of her free hand. "I love you", she said finally as her voice broke. "I love you so much that there were times when I thought it would consume me, so I ran, but I love you, Castle. I love you and I'm never going to run again. I just need you to know that I'm not going anywhere."

She barely finished her statement when his mouth crashed into hers, a frantic and bursting collection of teeth and tongues and lips, dotted with words like "love" and "forever" and "you", over and over.

He felt her leg snake around his back, then make its way downwards to push his boxer shorts down and away. It was the only piece of fabric left between them, and so much else had been torn away that it only seemed appropriate.

When they were both naked, their bodies moved together in a rhythm that set them on fire, touching everywhere, making up for lost time and too many tears shed between them. She grabbed him between them, hard and ready for her and he drew in a quick intake of air. "Please, Kate", he begged, stretching the words out as they escaped his mouth. "I'm going to lose it, Kate, and I need to be inside you."

She turned them over, flipping him onto his back and kissing from his mouth to his belly button, feeling him respond beneath her. She straddled him with purpose, and they looked into each other's eyes for a long moment before she took him inside her, slowly allowing him to fill her. They both released a cacophony of moans and grunts and words, some primal, some romantic as they began to move together. She rocked back and forth, controlling much of the rhythm and depth of their movements.

Kate leaned forward while they moved with each other and sought his mouth, anchoring herself with her arms on his chest. He surprised her by pushing himself up so they were sitting together, her in his lap, wrapped around him. They wrapped their arms around each other for dear life, mouths meshing easier in this new, incredibly intimate position as they met each other, push for push, thrust for thrust.

As they began to come undone, their movements became quicker, uneven, and their kisses were more like messy connections from mouth to mouth. They whispered each other's names in between noises that indicated just how close they both were.

Kate started moaning loudly, splaying her breasts against his chest as she grabbed for him, wanting to be as close as humanly possible in this moment. She bucked against him and bit his shoulder and he knew she was close. He wasn't going to make it much longer either. The romantic in him, the writer in him was holding out for her. He wanted them to take that trip over the edge together, to scream each other's names while they collapsed around each other. Her nails on his back interrupted his thoughts and he held her close while she pressed her face into his neck and shoulder, licking and sucking as he felt her squeeze around him.

She came with an intensity that pulled him with her, and slick with sweat, they kept their mouths connected as they rode out the intense breakers together. As he let go inside of her, a surge of electricity like he had never felt before took over him. It was laced with passion and love and connection, as well as the sedate haze of post-coital bliss.

They lay down together, remaining wrapped in each other's arms. As their breathing slowed and returned to normal, they lazily kissed and touched, moments from being overtaken by sleep. As he held her, tracing figure eights and hearts on her back, he felt like the luckiest man in the world. If anything, he had learned that the past doesn't matter. It reminded him of something crude his mother had told him once, in reference to his dance with Beckett. She had said "Honey, if you've got one foot in the past, and one foot in the future, then you are pissing on today." At the time, he had understood the sentiment, but never how it applied to his own life until he was laying in Kate Beckett's arms. Tomorrow would come, and they would deal with it together. Yesterday might have consequences, but there was nothing they could do about it now. In the present, they were lying in each other's arms, and that is really all that has ever mattered to either of them.

Kate smiled as she felt him running his fingers along her back and neck. She was sated, exhausted, and ready for sleep, but she was fighting it so that she could continue to feel the amazing sensation of being touched by him. She wouldn't allow herself to think of wasted time or opportunities missed. There was no point, at least not tonight. She was sure there were things that would be spoken about as they traveled this new road together, but she wasn't lying when she said she wouldn't run… No, she definitely wasn't going anywhere.

As lethargy and sleepiness finally painted itself over Kate Beckett and Rick Castle, they were on the same page. They were devoted to being in the present with each other, to exploring this new and amazing facet to their relationship. They were also committed to never, ever again doubting the deep, penetrating love that existed between them and that would save them, for no amount of darkness could make its way between the light that ignited when they were together.