A/N: Okay, so I have been hiding this particular story since the summer. I still don't know how I feel about writing M stories and had been hesitating with putting this out into the big, bad world. But in light of "Cuffed," I figured it was time to toss it into the deep end and hope it learns how to swim before it hits the bottom of the pool or ocean or whatever body of water I've cruelly thrown it into.

Disclaimer: Kate Sargeant just got promoted to a series writer. I didn't. (But CONGRATS TO KATE! We look forward to what you bring to the series!)

She had gone to bed early, dozing off as soon as her head hit the pillow. He had said he'd be up in a few minutes, that he just needed to finish this last chapter before he shut down for the night. But it had been almost thirty minutes and he still hadn't made the move from his study into the bedroom. She stretched her arms over her head and something jingled. Testing, she moved her hands again. Another clink of metal against metal.

"What the…" she mumbled. She tried to flip onto her stomach to investigate the noise, but her arms got tangled in each other. After a moment to verify that she was in his apartment, in their bed, she calmed down. A little. It was still unexplained as to why she was handcuffed to her own headboard.

Deciding to take a chance, she yelled out "Castle!"

"You called?" The familiar voice came from somewhere near her ear and made her shiver.

She rolled her eyes in the dark and was fairly certain that he could still see it. "Yeah, I called. Want to explain this?" she asked, shaking her hands to illustrate exactly what she wanted explained.

"Sure. Just seeing how you react under pressure. And believe me, Detective," he said, with a whisper that made her skin tingle, "I plan to put you under a lot of pressure. How much can you take before you break?"

She wasn't sure if she should smack him, if it had been possible, or jump him right then and there. Kate waited until she was certain her voice would come out steady and answered. "Castle, I'm a trained detective. I know how to handle an interrogation."

The mattress sunk as he sat near her hip. His hand settled on her thigh, his fingers brushing the junction of her legs. She squirmed and heard a chuckle from him which only caused her to glare in his general direction.

"So, you can handle anything I throw at you? Absolutely anything?"

Kate deliberated for a moment, then nodded, calling his bluff. "Yeah. You're on."

His hand left her thigh and she had to bite her lip to stop the little groan of sadness. She rolled her head, loosening muscles that had tightened. And gasped once her head had settled back on the pillow.

Castle was running the very tip of his finger along the arch of her foot. And, damn it, he knew that was one of her few ticklish spots. She nearly drew blood from her lower lip as she pinched it between her teeth in an effort to not move as he tortured her. It went on for about a minute, then, blissfully, he removed his finger from her foot.

She let her breath out, her chest heaving up and down as she relaxed. Between deep breaths, she huffed out, "Is that all you got?"

He crawled up her body, pushing her camisole up as he did. He placed open-mouthed kisses on her stomach, his lips coming close to her already pebbled nipples. There was a moan caught in her throat as he brushed the top of one.

"Do I feel you slipping, Kate?" he muttered, cruelly close to the sensitive flesh.

She pulled her arms down as far as they would go, clenching her teeth. "No. Just fine."

Castle rolled off her, placing a kiss on her cheek. She took the moments with him away from her, without his scent making her go crazy, to steady her breathing and take stock. Her body was tingling and she was pretty sure that if he decided to touch her, really touch her, she'd break.

"Last chance, Detective. You can give in right now and we can call it a draw. From here out, we get serious."

"Not. A. Chance."

He pounced, the motion making her shoulders sing as her hands caught on the headboard. But the minute pain was forgotten when he began to attack her neck. She shifted her head back. Her breathing, which had been so level a few seconds ago, was back to labored. His teeth nibbled on her pulse point, moving down to her collarbone while his hands worked on sliding her underwear down her legs. She lifted her hips to help him, pressing her breasts into his chest.

She regretted the movement immediately. Her control snapped. Her eyes rolled back as she groaned. "God, Castle, you better do more than kiss me."

He shimmied back up, pressing her head into the pillow with a kiss. "You didn't last long."

"Damn it, Castle…" she managed, twisting her arms to try and free them. "Uncuff me."

His laugh vibrated against her stomach where he was placing kisses. "I think I like having you at my mercy. Nice change to our normal arrangement." He looked up, his eyes sparkling with humor. "What exactly do you want me to do?" he waited a beat, then said, "Other than let you free, of course."

"God, do I need to spell it out for you?" she moaned, tossing her head on the pillow, tangling her hair.

He lifted himself over her face, kissing the tip of her nose. "Please."

She raised her head up, catching his lower lip in her teeth and nibbling it gently. "I need you inside me. Right now or I swear you'll never be able to again."

"Oh…" he drew out. "Well that would certainly be a tragedy. As I do love being inside you."

Slowly, he pushed himself into her and received a long moan from her as her body arched up. "God, Castle." She nearly broke right there, with him just lying on top of her, not moving. Her breath choked out, hitched back in.

"Kate. Do you even realize-"

"Yeah, I do." She tilted her hips up, urging him on. "Except there's the small problem of me not being able to help you realize it further."

As he pulled out, he placed butterfly kisses on her jaw. She took her chance. Rocking her body, she managed to roll them both over, ending with her straddling him, leaning over him with a grin.

"You are so good."

She mirrored his kisses along his jaw line. Her shoulders were screaming from the sudden movement and the handcuffs were tighter around her wrists, but for the first time in the night, she was in control. "You have no idea."

It only lasted a moment. He flipped them back over. To punish her, he pulled out completely. A pout graced her face. "Oh, Castle, don't be like that."

He took his time. There were deep kisses, ones that made her moan into his mouth and bite at his lower lip. There were teasing, light kisses that had her shivering with the intimacy of them. Between their meeting of lips, Kate managed to get a few words in.

"Castle, you…need to let…me go."

He smiled against her cheek, then shook his head a little. "No, I don't. Turned tables aren't much fun for you, are they?"

"I'm serious." She pulled her head back into the pillow, trying to ignore the desire still running rampant through her body and fix him with a serious glare. "Uncuff me."

Castle stopped and took a moment to consider her. He weighed the idea of ignoring the deadpan tone with which she had addressed him with actually letting her go. He enjoyed playing with fire, but he had never wanted to push her too far, fearing that she would withdraw from the relationship completely.

She watched the though process play out on his features. His brow furrowed, he bit his lip, gave a little head nod once in a while, a shrug. It was endearing, really. But her arms were starting to hurt and she was definitely going to have bruises on her wrists. She raised a brow when he gave a definite nod.

The expression left her face an instant later as he filled her completely. He didn't move.

"God, Castle…" she moaned, biting down on her own lip. "Let me go. I want to-"

He shifted, reaching over to her bedside table and picking up the little silver key. She was pleased to see his fingers shaking as he freed her hands, massaging her wrists to work life back into her fingertips.

She didn't wait a second once they were free before pulling him back over her. In the middle of a kiss, she grabbed handfuls of his thick hair and pulled him away from her.

"You pull another stunt like that, I will shoot you."

"Understood. But it was fun, right?"

She decided that the most effective way to shut him up would be to kiss him. She pushed her head up, swallowing his moan. As he nudged her legs apart, she hooked her ankles around his hips, pulling him toward her. The angle had him hitting her super-sensitized skin with the smallest push forward, her short nails digging into his shoulders.

"Castle, God!"

He paused his motions, whispering in her ear. "Which am I? Castle or God?"

Between gasps, she muttered, "You'll be dead if you stop again."

He tried to go slowly, to enjoy the pent-up sensations from his little experiment, but Kate was impatient. She squeezed her ankles, pulling him closer, her body arching upward as he whipped them into a breathless frenzy.

She broke on a strangled cry, her hands scrambling for an anchor in the sheets. Nothing gave her purchase so she dug her fingers into his shoulders even as he let his head fall onto her shoulder with a groan.

Neither of them could manage words for five minutes. The sound of their breathing filled the room before Kate shoved Castle off her.

"I don't know if I want to do that again or throw my handcuffs away so you never get the chance to use them."

He rolled onto his side, trailing a single finger down her arm, still thrown up over her head, resting on the cascade of her dark hair. "I must say that, as fun as it was having you under my control, I do love it when you can participate fully."

"We'll see if you find it as amusing when you wake up handcuffed to the headboard, Mr. Castle."

Castle placed a light kiss to the corner of her mouth. "Threats, Detective? You going to follow through with that?"

Her lips turned up in a sleepy smile. "It'll have to be a surprise."

A/N: I'll be hiding under my bed until at least Monday now.

I hesitate to ask for reviews, but if you feel like giving them to me, do so. Be nice.