A/N: Please note the rating change for this chapter.


Prompt: What if the kiss in 3x13 (knockdown) had escalated into more?


She's sucking on his tongue and using every ounce of diminishing willpower that she has not to grind down on the thigh pushed between her legs. The guard by the door isn't moving, still glancing to them from time to time, but she saw him waver when she and Castle were kissing, an eyebrow of intrigue arching, and she thinks if they can just gain a little more attention, go a little too far-

"Kate," he gasps, groaning when she abandons his mouth and turns to his neck, laving her tongue over the pulsing skin beneath his jaw. She hates to admit it, but god does he taste good, he feels good, better than she ever imagined. "Gotta stop."

"No," she growls, nipping hard at his jugular. They're up against the nearest wall she could push him into and she gasps when he spins her, presses her flat against the chilled concrete and grunts when her spine automatically arches for him. "We're close. He'll stop us soon."

"He better," Castle warns her as he leans in again, punishing the skin of her neck just as she did to his, marking the column of her throat with the heat of his tongue and the drag of his teeth, and she can't help but squirm and mewl against the drugging sensation of his mouth on her.

"More," she demands, hooking a leg at his thigh, stabbing her heel into his calf muscle and jerking his crotch against her and oh - oh, he's harder than she thought. "It - it has to look authentic," she gasps in explanation, but she doesn't know if he's listening as he takes a split second to study her face. She doesn't know what he sees, but it must be enough because he dives back in, takes her mouth and kisses her until she's moaning and rocking her lower body against him.

Her head falls back against the wall as his hands grab her hips, his grip bruising around her bones while he tries to slow the frantic roll of her lower body, guiding her into a calmer rhythm, a burn that is even more intense than before.

"Don't stop, don't stop, don't-" she's babbling, getting off on the hard press of Castle's body against hers, and she really hopes he's watching the guard like she told him to because all she can see is the bursting sparks of white light behind her eyelids.

His body has been a taut line of restraint since this little ruse of theirs made an escalation from kissing, but the wave of her body undulating against him eventually has him thrusting sharp, hitting her just where she needs, increasing the sinful friction sizzling between them, and she keens low in her throat as she tightens the arms around his shoulders, stabs her nails into his back.

"I want my mouth on you," she says, loud enough for the man only a few feet away to hear. Castle jerks to a stop, looking horrified under the lust clouding the dark blue of his eyes. "It'll - will work," she pants for him alone, but he shakes his head, an adamant 'no', and she growls at him, but at the feel of his hand slipping under her shirt she quiets.

"Castle," she breathes as the heat of his palm skims her ribs, ventures higher up to slide under her bra, cup a single breast and squeeze the taut peak of her nipple.

She chokes on another gasping breath as he leans in close again, crowding, towering over her, and traces his tongue along the shell of her ear.

"Too much?"

She shakes her head, forgetting for a shameful second about the boys they're trying to save, about the fact that she has a boyfriend, about everything except him and his mouth and his hands.

"Don't stop," she repeats, turning her head and stealing his lips once more, shoving her tongue in his mouth and memorizing every second and taste and sound she can evoke as she works her body against his.

She goes rigid when he teases the waistband of her slacks, toying with the button, but she bucks her hips after a moment of stillness, waits for him to slide the zipper down. She expects to be hoisted up, but he merely tightens the thigh already curled around his and slips his fingers down, down past the soaking black satin of her thong, down into the drenched heat of her core.

"Kate," he groans into her cheek, experimentally brushing a finger through the wetness of her folds, and she arcs forward, nearly sending them both tumbling.

His tongue in her mouth matches the rhythm of his fingers circling her clit and she's practically keening by the time he finally slides a finger inside of her.

"Fuck," she hisses, biting her own lip - or maybe his, she isn't sure - and crying out as he withdraws only to add another. She can already feel the lapping waves of an orgasm licking at her abdomen, blurring at her vision, and she buries her face in his neck, rocks hard against his hand and clenches her fingers in his hair.

"Let go, Kate, I've got you," he's murmuring over and over into her hair and she's on the verge of sobbing because it's so wrong, it's all so wrong, but she's never been this wound up with the scalding heat of pleasure before. She's never seen so many stars exploding behind her eyes as she falls.

The whole point of their act was to cause a distraction, she's been purposely loud since they started making out against the wall, but when she comes, she bites back her scream, releasing only a strangled whimper against his throat.

"Okay this has gone on way too long, you two are committing a disgusting act of public indecency and I-"

She has the guard knocked to the ground before he can finish. She's breathing heavy, gripping her gun hard to conceal her shaking hand, and she's afraid to look at Castle. But she sucks in a gulp of air, turns to see him wiping the sticky evidence of her on his pants.

Her mouth feels dry, words getting stuck, and she wishes more than ever that circumstances were different and they could go to her apartment, spent the entire night in her bed.

"Castle-"

"Let's go," he murmurs, eyes downcast as he strides past her, and she curls her fingers over her swollen lips, forces herself to focus as she follows after him.


Josh is at her apartment when she finally arrives home later that night. She doesn't have an explanation for the collection of deep purple bruises staining her neck. He doesn't ask, seems to already know. He leaves and she should feel guilty, hurt, but her thoughts are plagued by only one thing for the rest of the night.

She dials Castle's number.