Summary: It's a late night. Provoked, Beckett decides to give Castle a taste of his own medicine.

Rating: Almost M. But I'm feeling nice, so here's a gimme for the kiddies.

It was 10:06. Kate Beckett typed yet another case report, submitting some of the day's last paperwork into the system. Her head was killing her, phones were ringing, and she wondered where Castle had gone. Even in this racket, it could be louder; Rick Castle had a notorious mouth. He just wouldn't shut up.

Somehow, it filled the silence that Beckett had. She liked quiet, but at the same time, cacophony was essential to her existence. Having that idiot nearby around the clock was oddly refreshing.

The detective pressed the back of her forehead and yawned. She needed caffeine and she needed it now. Pushing her chair back, Kate strode into the hallway, fishing around in her pockets for extra change or bills. Her slender hand closed around two quarters, and she began to lift it out. Along the way, a slightly calloused, masculine hand snared it.

With her hand pressed to her waist, Beckett barely struggled. She was strong, as an officer. But somehow, Castle was stronger.

"Need a fix, Kate?"

Rick Castle's voice was intriguing, and usually annoying. But at that moment, it had turned dastardly, seductive, and downright delicious. She resented his vocal cords for sending her stomach falling to the floor. His breath was warm upon the back of her neck, and, resisting the urge to moan, Beckett twisted around to face him. The change fell out of her hand and onto the floor tiles.

Kate swallowed, holding Castle's sapphire gaze with her usual irritation. "Yeah, actually. It's late." She knelt down to retrieve the two quarters, willing the blood not to rush into her cheeks. The hollow noise that the falling quarters made in the soda machine barely bridged the sultry silence. The detective glanced over at the writer, who was biting his lip and looking at her waist.

Beckett felt like gagging, or following natural human instinct and jumping on top of the man opposite her. She opened the can instead and plastered her lips on the cold aluminum. It didn't feel quite right.

"So, Beckett," Rick mumbled, dropping his expression. "How's... work?" He ran his fingers through his hair in a laboriously slow fashion.

Kate clenched the cola until her knuckles were white. She forced herself to sound generally casual. "I was doing some paperwork, you know, the usual. Didn't see any action today." She flexed her neck, delicate muscles pulling and stretching beneath the perfect flesh. Castle tore his eyes away.

Didn't see any action today...

The writer felt the familiar fire burn beneath his skin, and everything seemed to move sleepily. He stepped forward and put a single finger beneath Beckett's chin, dragging it slowly towards the edge. She looked up, face burning. Both hearts pounded as Castle leaned foward. Their faces were inches apart. He could feel her breath, bated and hesitant, catch against his.

Castle waited there, his eyes half-lidded and patient. Periphery revealed an unfamiliar look on his muse's face; it was one of surprise and near-lack of confidence. She was graceful and sure in her everyday movements and decisions, and yet she quailed at the mere thought of a kiss. Wantonly, he bridged the rest of the distance and felt her connect with him for the very first time.

Kate Beckett felt her mind go blank. Her eyes went wide, and she dropped the soda on the floor between them. They were almost backed against the wall, so the detective, always on her toes, used this for leverage. She pushed against the wall, giving her space to take the active position. The pair was apart again, and Castle sank emotionally as she licked his taste off her lips.

She continued, voice agonizingly normal. "And you, Castle? What have you been doing all day?" He thought that Kate sounded like one of those over-the-phone hookers, the kind with the amazingly beautiful voice. Normally, she sounded like something of a bitch in his mind. A smokin' hot bitch, anyway.

"I... I've been writing."

The detective stared down at the puddle of brown cola pooling on the floor where they'd stood not a second before. "Oh? How's your book coming along?"

"Oh, you know, the usual," Rick said caustically, imitating her. She whirled on him. "The plot's at a low point. Protagonist does some paperwork, gets a soda..."

Beckett pushed him against the wall, dropping her arms at her sides. "And don't forget. She finds a better fix." Her whisper was a warm wind in his ear. He gulped.

Castle didn't have time to raise his eyebrows in that quirky little way before Kate's face was half an inch in front of his. Their foreheads touched, his broad one and her soft, smaller one. This time, it was harder to tell who closed the short space that seemed miles long.

They fought each other, kissing messily and aggressively. Beckett thanked God that the door to the office was closed as Castle made a dark, animalistic noise in the back of his throat. She hadn't realized her hands had wandered as though they had minds of their own. Her first two fingers were stuffed in one of his belt loops, and the other hand was under his shirt.

Her heart stopped and her brain paused as Rick's tongue, offhanded and sudden as the man himself, probed the line of her bottom lip. She sighed desperately and pressed her hips against his, battling him again for dominance. They were having a silent conversation, often punctuated with stark, human noises.

The writer pulled them apart to moan. Kate continued instead at the nape of his neck, right where his collar was always jauntily unbuttoned. "You're such a... damn... tease..." He felt his body whirr and spark as her fingers crept dangerously lower.

"I suppose every muse has her quirks," she breathed, each word puffing against his collarbone. Castle choked. He tried to form a witty, well-thought out reply, but none came.

Beckett continued her wicked instrumentations, inwardly amused at herself. Her last boyfriend had been something of a slow starter, so she'd had to learn sometime. The fact that she had her own experiences to rebut all of Castle's was quite hilarious, truly. Accidentally, she found herself chuckling almost evilly.

Beckett, you bitch, you succubus, Rick thought, twisting and shivering underneath her amazing hands. It had been a while since someone had prodded him right back. It was irresistibly ironic that that someone was Kate Beckett.

She stood, trailing her fingerprints all over his sides.

"What-? Why-?"

Kate Beckett straightened her Oxford as she began to walk away, her professional cockyness returning. She turned around, the devilish grin- Castle's favorite- the last thing to fade. "In the end, your protagonist prefers her soda. But she hasn't been swayed just yet. She hasn't had enough time to taste the rest of the competition."

The writer groaned in disappointment and sunk against the wall as the office door slammed vindictively. Now he'd have writer's block.


And there goes my very first Castle fic! I loved writing this whilst I took a break from P&OJ. Reviews would be greatly appreciated.

After all... I want to know if anyone'll read the sequel.