Disclaimer: I don't own Castle.

A/N: Season One Tag! Because this was a Christmas present for Sav that I was a bitch about and definitely just got around to finishing. I'm sorry I'm a horrible person.

This is M for a reason.

Her chest aches. The air won't fill her lungs. Betrayal burns in her blood. She asked. No. No, she told. She told him. She'd thought he was different now, she'd thought he would respect her enough to drop it. But he's still the same jackass from that very first case they worked.

She's been sitting in the same spot on her couch for an hour and a half. As soon as she walked in the door, her body gave out here and she can't find it within herself to move. Her brain is whirring, her chest throbbing and she wonders how it came to this. How did it become this when she'd been talking to Will – making sure he was okay – just hours ago? How did she go from smiling over sprinkled doughnuts to sitting catatonic on her couch?

Castle. It's his fault. He did this. She doesn't even know how she feels. Hurt. Angry. Betrayed. Pissed the fuck off. It feels as though he's plunged a knife straight into her, twisting the handle just to cause more pain. And maybe that's partially her own fault, maybe she started to care. Maybe she started to trust him.

He ruined it. Ruined whatever partnership they potentially could have had. Whatever friendship she thought they were building, he trashed it all. And for what? What did he think would come of his nosing around? No. She's done. She's done. She's done with Richard Castle.

Why does it hurt so much? She shouldn't care. She should be relieved to finally have a reason to kick him out but she's not. She's not because he did the one thing she told him not to. He dug up the one thing she'd buried.

Her mother's case is off limits. He disrespected her wishes, disrespected her and the anger bubbling in her stomach becomes a steady boil. He doesn't get to do this. He's not in charge of her life, he's not even part of her life. She will not sit on her couch for one more second and let thoughts of Richard Castle churn like acid. She's done with him and he's going to be done with her. She'll make sure of it.

There's no grand plan, no idea that's motivating her actions. The more she stews on it, the angrier she gets and the angrier she gets, the more she just needs to burn it off. She wants to yell, maybe shove things and break things. She doesn't know why or how she ended up here. She just knows she has to make him leave her alone…for good.

When Beckett finally faces his door, she slams her palm into it and then balls her fist to knock. Loud. Hard enough to leave her knuckles stinging.

He takes too long to answer so she does it again. She forgets in that moment that he shares a loft. She forgets that he could be out or have company. Her body is burning, blood zinging through her veins, she has too much energy pent up. Her manners are gone and the second the door flies open, her morals jump ship too.

She doesn't yell or shove him or even march into his loft and childishly stomp around looking for something to throw at his face. Something propels her forward. Maybe it's purely fueled by anger but there's heat in it too and for the split second it takes her body to collide with his, she's more than a little vulnerable. But then he's warm against her and her mouth is crashing into his, teeth scraping and she has no idea what she's doing.

Her anger wanes, her kiss softens when his lips move in tandem with hers and she almost forgets everything. Until he's gripping her arms, forcing her to step back and her eyes open to a storm of blue swirling in his. She watches his brow furrow before her gaze darts down to his mouth.

"Beckett…wha-"

"Shut up." His hands fall away from her and she uses the freedom to crowd him, daring him to back down. Some small part inside of her begging him for an apology that never comes. Her name falls out instead and the hurt she felt, the stunned shock, all of it whirls inside her once again. "Just shut up, Castle."

She's pissed again, falling against him heavily, forcing him to stumble as she sinks her teeth into his bottom lip. Hard enough to make him groan before sucking it into her mouth, laving her tongue over the small speck of blood she drew to the surface.

The switch is flipped. She's not the only one. He isn't idle, he isn't confused anymore. Castle kisses her back, hands roaming down her sides, over her hips, sliding around to cup her ass and this isn't what she came for but fuck if it isn't what she wants. Fury makes her impatient, has her pulling at his shirt, fingers scraping his skin in her attempt to tug it up and off. Her attempts are futile and forgotten the moment he grips the back of her thighs and hoists her up.

Everything has fled…everything but the betrayal and the need. It's a desperate, hot, need burning between them, her hips rocking against his with every step he takes. She doesn't stop. Can't stop or she'll start thinking again. He tastes of whiskey at the corner of his mouth, intoxicating and sharp on her tongue. When his head turns she feels no loss, the scrape of his stubble sets off a new wave of arousal.

The air is thick when he drops to the mattress, perching on the edge and holding her close. She doesn't want to be close…she doesn't want to be in his bedroom. Her stomach is in knots with the shock of it. She forces herself not to look, to focus, to grind in his lap until her eyes roll back and his hips jerk up to meet her. She's panting before his shirt hits the floor, desire clenching in her gut.

Hands tear over fabric, seeking flesh and she gasps when her fingers make it beneath his boxers. Just as quickly as she cups his length in her palm and squeezes, she's pulling back. Abandoning him completely. Leaving him disheveled and swaying to stay upright. His chest is distracting…she's not sure how she can be attracted to him after what he did but she is. She hates herself for that. There's heaviness in the room, an anger brimming just beneath the surface. She's letting it out.

She undresses quickly. Piles the pieces of clothing neatly in a nearby chair so she won't have to hunt for them. He mumbles something about her beauty when her breasts are freed from her bra and she ignores it. He's a breast man. Signs chests. Not shocking the sway of hers has him spilling lies.

More lies. She doesn't trust him anymore…and it hurts. It hurts to look at him. So she doesn't. She stops herself, drops her gaze, runs her fingers along the waistband of her panties and decides that he hasn't and never will see her completely bare. They stay on.

She straddles him before he can say anything, pulling on his hair and making him tilt his head back. She doesn't want his mouth this time. Her lips press to his ear as she snakes one hand down to free his erection.

"You're an ass," she whispers against him and in some language known only to them in this moment, that's his permission to touch her back. To grip one hip and slide her panties to the side, his fingers lingering, swirling around her clit until her back arches and she growls at him. "Stop."

He does and then he tries to roll them, tries to make this more than it is. Playing a part in a charade she has no plans of falling victim to. She clenches her thighs, digs her nails into his shoulder.

"No…like this." No more playing. No more games. She thrusts her hips, arousal coating the hard hot press of him against her.

"Beck-"

She slaps one hand over his mouth, uses the other to guide him in place. Part of her knows what he's about to say. Something about the condoms she assumes are kept nearby for his sexcapades. That just makes her angrier. She's not thinking, she'll regret it tomorrow. She drops onto him in one quick move. Rough, biting her lip at the feel of him stretching her.

He grunts against her palm, fingers digging into her hips. That's what she wants, she wants the roughness. He could stop her, he could end it but he doesn't. His hips jerk and they both groan. She sets the pace, quick and dirty. She wants it over in a hurry, wants her anger to burn out and to just move on.

Their bodies slap, her hand falls away from his lips and she doesn't okay it but somehow his mouth is on her breasts. Teeth scraping her nipple as he's thrusting to meet her, hands searing against her skin. Too much.

Beckett clenches around him when he tugs at the short locks of her hair, her body on the edge. She wants to make him come first. She wants that moment of power. But she loses it the second his fingers slip between them, the first pinch and roll of her clit and she's shattering around him. Embarrassingly quick. Her walls clenching, mouth gaping, her body strung tight, back bowed and not a sound between them except his heavy breathing.

And then he's gripping her tight, sliding deeper, pushing in until she's whimpering and falling limp. Anger absorbed, body too exhausted to fight it any longer. She hates it but she buries her face in his shoulder as he drives into her. Over and over. Sloppy and quick, no finesse. She keeps her eyes screwed shut and her face pressed into his skin, she can't look at him. She can't look at his room.

She whispers his name. Rick. Not Castle. A desperate plea and he stills beneath her, body rigid as he comes undone. The sense of pride she expected to feel at having the control is nonexistent. The warmth of him flooding inside her, the taste of his sweat, the last shred of anger…the weight of what she's done.

She pulls back slowly, hearing him gasp as she wiggles in his lap and then she's sliding off of him. Her thighs burning as she stands and quickly rights the panties she's just ruined. Silence stretches between them, she can feel his stare as she heads for her clothes. She doesn't plan to break it. She's fine with leaving.

She's not fine at all. He doesn't move. Not a sound or a single shift of his body until she's frantically tugging her pants on and stuffing her feet into her shoes.

"Kate…"

She ignores him until she's covered, refusing to look.

"Beckett, what was that?" Now he's moving, adjusting himself. Standing in an attempt to figure out what the hell happened.

She's still trying to figure that out herself. Her eyes meet his and it all comes back but this time it's paired with a lump in her throat and a realization that maybe it hurts because she saw them doing this differently.

"You got what you wanted." It's time to leave, time to move on. She turns for the door, she can let herself out. "Now stay out of my business."

Below is a note to someone very special to me. She deserves this little surprise.

To Sav,
You're my very favorite smut buddy, my hell buddy. The one I always always share dirty Caskett thoughts with because I know you'll just push me until I write it. Even when it's porny. And you make it worse ;)
Despite the ups and downs we've faced in the previous year, the previous few months (I wrote this awhile ago sorry I'm posting so late) you're still there for me. We don't agree on a lot of things and I'm a complete bitch to you more than half of those but somehow we make it work.

I cannot imagine life without you in it. I'm so thankful we started talking. There's not a single day that goes by where I don't find something I want to tell you about or a photo to share. We were brought together by Castle, by these characters we cherish, but you've been an amazing friend, one I plan to keep for a very long time. Thank you so much for putting up with me and my constant whining the last year. Thank you for encouraging me in writing this and supporting my decision to post it. I adore our friendship, I love you, you're important to me in a way I can't explain and I'm very glad you exist.