Bonus points if you spot the X-Files reference.

She watches Castle through the break room window as she makes herself a cup of coffee, can't stop the smile that blooms across her lips. He's perched on the edge of Ryan's desk, hands and face animated with a certain to be embellished tale, and it feels so much like it used to that she wants to laugh at the absolute absurdity of it all. Because it's so very much not like it used to be.

There's an undercurrent of awkwardness in their interactions. It pushes on her body, weighs her down. Reminds her over and over that no matter how well they may fake it at the precinct, their relationship is damaged. Broken. The smile drops off her lips and she dips her head, reality crashing down around her shoulders yet again.

Six weeks. Forty two days spent pretending that her heart isn't shattered, that it doesn't hurt to have him at her side - close but never close enough - day after day. Her armor is pierced and cracking, splitting apart at the seams. The effort it takes to piece herself back together every morning, to become Detective Beckett, has become almost more than she can bear. Something has to break. Soon. And she's terrified that it's going to be her.

"Daydreaming again, Detective? Better not let Gates catch you."

The low voice, rich and smooth and full of Texas, startles her, sends the forgotten spoon clanking against the ceramic rim of her mug. Setting her shoulders, Kate turns and faces the recent addition to their squad, Detective Mark Newsom. Newsom, his slender frame propped up against the doorjamb, gives her a sloe gin grin, bright and sweet, and she feels her own lips tug up in response to his effortless charm.

"You gonna turn me in, Newsom? Not a great way to endear yourself to a new squad."

"I wouldn't dare." He pushes off the door frame and saunters toward her, eyes twinkling merrily. Kate catches a whiff of his too strong cologne as he reaches around her for a mug of his own, his arm brushing deliberately across her shoulder. "I'm still hoping you'll take pity on me and save me from the special brand of hell that is being partnered with Johnson."

She laughs lightly and takes a subtle slide to the right, distancing herself. "He's not that bad."

"The man smells like bacon twenty-four hours a day, Beckett."

"I'm not going to ask how you know that."

"Probably best that way." He turns to face her and she feels his gaze sweep slowly over her body, warm and assessing. Holding her mug in one hand, Kate crosses her arms and squares her shoulders, closes herself off. He picks up on her signal with a slight nod, eyes cooling in an instant. Leaning back against the counter, he shifts out of her personal space. "Help me, Detective Beckett. You're my only hope."

"Sorry but I've already got a sci-fi geek on my team and I'm pretty sure one is my limit. More than, actually. "

Newsom chuckles, his green eyes crinkling as he shrugs his shoulders. "Well, you can't blame me for trying." He grins at her again, crooked and friendly, and moves toward the door, mug raised in a salute. "Let me know if you change your mind, though. I've gotta get away from that man before he completely ruins my love of pork."

Kate watches him go, mug cradled to her chest. He looks back at her as the rounds the corner and she gives him a tight smile before turning away, eyes slipping shut. A wave of guilt crests in her chest and she sighs, running a hand roughly through her hair. Ridiculous. Draining the rest of her rapidly cooling coffee, she tries to shake it off, pull herself back to the present.

Castle falls in step with her as she exits the break room, his voice tight when he speaks. "I need to talk to you."

"Okay. Talk."

"Without an audience." He throws a sharp nod at Ryan and Esposito who immediately launch into a very loud, very fake conversation.

"Castle, I have work to do."

"Beckett." She stops short when she feels his fingers close around her wrist, her breath catching hard in her lungs. It's the first time he's touched her since they broke up and her body instantly reacts to him, heart hammering wildly against her ribs. Kate whips her head to look at him, eyes flicking down to his hand and back to his face. His fingers tighten around her wrist for a moment and then they're gone, her skin left burning. "Please."

Wordlessly, she turns and heads for the stairwell, swiping a folder off her desk for effect as she goes.

Her heels clatter loudly on the concrete steps, the sharp report echoing inside the enclosed stairwell. She can hear Castle shuffling behind her, his booted feet hitting the steps heavily. They move in silence and Kate uses the time to prepare herself, shore up her defenses. She stops on a landing three floors down and turns to face him, brow raised.

He stands two steps above her, staring down at the top of her head, mute. His face is closed, lips pressed into a tight grimace but his eyes. Oh. His eyes are shining with something she can't quite identify but whatever it is scares the hell out of her.

This is going to hurt.

They're curled together on her couch, her legs a bridge across the valley of his lap. His fingers twirl through her hair over and over, relaxing. Hypnotizing. She's warm and content, her body sinking into him, head resting heavily on his shoulder. Castle brushes his thumb along her neck, swirls a tight circle on the sensitive skin behind her ear and Kate hums low in her chest, nearly purring at the sensation.

"Mmm, that's nice." The words are honey in her throat, slow and thick. His laughter rumbles under her ear and she swats at him half heartedly, fingers lazily swiping across his chest. "Don't laugh at me."

His lips are soft and light against her temple; his fingers tangling in her hair as his other hand skims slowly up and down her thigh, fingers curling warmly against her bare skin. "Wouldn't dream of it."

She's still getting use to the feeling of being near him, touching him. Still marvels at the the way she's able to lose herself in it. The way her body slots almost perfectly into his. How his hands feel running across her skin, the smooth palms and calloused fingers soothing, calming. The serenity of their silences, long and comforting, words becoming superfluous. She shifts her body down, nestles more firmly into the cove of his embrace and sighs, happiness flowing warm in her veins.

"I have a little something for you," he whispers, breath rustling across her crown.

"I'd say it's more than a little something, Castle." She wiggles her hips, breasts brushing against his ribs.

"Okay, that's going in the next book." His lips dance down her cheek and she tilts her face into him, lets his stubble scrape over her lips. "You know how I love it when you talk dirty."

He groans when she nips at his bottom lip, flicks her tongue along the sharp ridge of his teeth. Shifting underneath her, he twists around and presses her into the couch with his upper body as he takes her mouth, tongue slicking across her lips, curling around her own. She rolls under him, smiling into his mouth when his hips buck. Need, hot and heavy, unfurls low in her stomach and her chest fills with delight at the way they're able to push each other to the edge with such ease.

"Here." He breathes into her mouth, fingers closing tightly around her own. She feels something bite into her palm, rigid and sharp, and sucks in a deep breath, body going still. A cold fist clenches in her chest, icy tendrils of panic and fear creeping down her spine.

"What's this?"

He grins at her, soft and amused. "It's a key. To the loft."

The key is oddly cool in her hand despite the suddenly sweaty heat of her palm. She pushes on his shoulder and he rolls to the side but the weight remains on her chest, heavy and oppressive. Kate closes her eyes and pulls in a shaky breath, tries to calm her racing heart. She focuses on clearing her mind. Castle's hand rests on her hip, a gentle pressure that she concentrates on. Syncs her breathing with the slow sweep of his thumb across her side. Inhaling fresh clean air, exhaling the anxious worry.

Just a key. She adopts the mantra, repeats it slowly in her mind. Let's the words flow together and wash over her, a clear stream of simple truth. Just a key. Not a reason to panic or run. Her heart rate slows as she breathes,

Kate opens her eyes to find Castle staring down at her, shadows of hurt playing across his face. She reaches out a slightly trembling hand and runs her fingers over his forehead, smooths the pads over the deep furrow between his eyes.

She wants to speak, assure him that she wants this, him. That she's just startled and unprepared but she's in this with him. But the words are stuck in her chest, lodged firmly behind her battered heart. Castle pushes out a sigh and drops his head, nose brushing along her cheek.

"It's a key, Kate." His voice is low and strong, calm. "I'm not asking you to move in or suggesting we start picking out china patterns. It's just a key."

"Just a key," she repeats, her voice thin and reedy. "I know."

"You don't have to use it," he whispers and she closes her eyes, the current of his breath skirting over her cheek. She feels the iceberg in her chest start to crack, little pieces breaking off and floating away, melting under the warm press of his body against hers. "Just keep it, Kate. I want you to have it."

Her fingers curl around his bicep, the key pressed hard between her palm and his arm as she tugs him back down. He comes willingly and she wraps her arms around his broad shoulders, cradles his body tightly to her chest. The words are still hanging there, crowded behind the wet knot of apprehension she can't manage to untangle, so she uses her body. Tries to tell him with the press of her lips and the glide of her hands. Closes her eyes and hopes he understands.

Kate moves back as he takes the final two steps down to the landing. Distance. She has to maintain the carefully measured distance they've been tacitly observing for six weeks. Never any closer than they absolutely have to be. It's the only way she can control her rebellious hands, her palms constantly itching with the need to reach out and touch some part of him. Any part of him. She folds her arms, folder hugged between her forearm and chest, and wraps her fingers tightly around her own biceps, nails biting into her skin.

"If you have something to say -"

"I can't do this anymore."

It's a fist to the solar plexus. Her body bows around the pain, spine curving, shoulders rolling forward to protect herself from the next blow. Blood rushes in her ears, a sick feeling of deja vu swirling in her head. This can't be happening. Not again.

"What?"

He takes a step forward and she wants to move away but her legs won't respond, feet rooted to the spot. "It's too hard, Kate." Her heart stutters to a stop. Starts. Stops again. He never calls her Kate anymore. Shit. "I love you. I love you and I can't sit around and watch you move on." She shakes her head, hair whispering across collar, but he keeps talking, the dam broken. "I can't watch you pretend like we never happened. It hurts too damn much. I thought the work would be enough. That the satisfaction I get from solving a case would make up for the loss but it doesn't. It can't."

Castle takes another step toward her and she can feel the heat of his body pushing up against her skin. She burns with it; the desire to lean in and press the length of herself against him, show him what satisfaction feels like, sparking like flint against her heart.

"I know that what we had -" He stops. Swallows. She watches his throat bob as he works for the words. Waits for the knockdown punch. "I know it didn't mean the same to you but -"

The folder flutters to the ground as she throws herself at him, puts an end to his blasphemy with the slide of her tongue. Her hands scrabble against his back, nails scraping hard across the sharp line of his shoulder blade. He kisses her furiously, perfectly. He yanks her closer with an arm around her waist, the other hand tangling in her hair, fisting, directing the twisting curve of her neck. A desperate moan echoes around them and she has no idea whether it's hers or his but it's wicked sound, hungry and full of need and it makes her want to burrow inside of him, wrap herself up in the furor of his love.

A slamming door - above or below, she doesn't know, can't tell - wrenches her back to reality and she breaks away from him, her chest heaving. He stares at her with glassy eyes and swollen lips, awe etched across his face. She presses her fingers to her buzzing lips and he sways, body listing heavily toward her.

"Kate."

"I think you're right," she whispers, the words broken glass in her mouth, shredding her tongue. "Maybe it's best that you go."

He stares at her for a long moment before nodding. Her eyes close as he steps around her, the scent of his cologne drifting gently in his wake. She listens. Waits until his footsteps fade, until the heavy metal door clatters to a close to open her eyes, bend over and gather her scattered papers.

She couldn't watch this time.