Disclaimer: The only part of Castle that I own is the TV on which I watch the show.

Tuesday turns out not to be great for apartment hunting, at least for Beckett. It's fruitless and dismal. Wednesday is worse. And Thursday? After a string of not-if-this-were-the-last-place-on-Earth tours, she's ready to surrender to clinomania and stay in bed forever—or at least until Monday, when she has to go back to work.

Alexis is home from Colorado and Beckett has officially returned to the guest room upstairs. On Friday, Castle's daughter leaves early for a friend's all-day-skating-and-a-movie birthday party. Beckett gets up briefly to see her off, then climbs the stairs and goes back to bed. Some time later she's woken by a host of sensory stimuli. There's the squeak of a step, quickly followed by the smell of coffee, an unwelcome rush of cool air against her bare legs as someone peels back the bedclothes, and the very welcome sensation of that same someone's tongue on the skin just below her left ear.

"Morning, my little groundhog," says Castle, who has pulled the bedclothes back up over the two of them and is snuggled against her back.

Beckett sits up to drink some coffee, slides back down, rolls over, and swats him lightly on the shoulder. "Your little groundhog?"

"Ouch. Would you rather I called you my little woodchuck? Or whistlepig?"

"None of the above. And why am I suddenly a member of the marmot family, anyway? Among other things, I do not have buck teeth."

"Because you're burrowed in your bed and apparently do not intend to re-emerge until winter is over. Not that I'm complaining, since I'm your official co-burrower."

"I'm never going to find an apartment anywhere around here, Castle," she says, pressing her forehead into his chest. "I'll be riding the ferry every day like Melanie Griffith in Working Girl."

"Not true. You liked that place on Hester Street. It was great."

"It was six-thousand-dollars-a-month great, Castle. It should come with a butler for that. Way out of my price range."

"Not if I—"

"No. Absolutley not. We have talked this to death."

"Well, I think we should let the argument rise again, like Lazarus."

"I am not letting you pay for my apartment, Castle. That's final. End of discussion. Case closed."

"How about if you let me be your butler? I won't charge you a cent, and wait 'til you see me buttle."

Before he can describe his buttling prowess, which he almost certainly would illustrate with visual aids, Beckett's phone rings. She reaches for it and looks surprised at the caller ID. "Dad? Is everything okay?"

"Why wouldn't it be?" her father asks.

"No reason. Just, you know, you don't usually call me at—" she takes the phone away from her ear to check the time—"at ten-thirty in the morning on a weekday."

"Do you remember Mr. Harrison? Sam Harrison?"

"Sure, the Harrisons used to live down the hall from us. Why? Did something happen to him? I haven't even thought of him in ages."

"No, he's fine. He lives on West Sixty-Seventh Street now. He's widowed, three years."

"Oh, I'm sorry. She was nice. Took those baking classes and used to give me her experiments. So, what's up?"

"I had dinner with him last night and he was telling me that he's about to go to Brussels for a year, doing a consultancy for NATO. And his apartment will be empty. Well, it'll be furnished, because he's not taking anything with him, but there won't be anyone living there. I mentioned that you'd been having a hard time finding a place since you lost yours, and he offered you his."

"Dad, that's by Lincoln Center. It must cost a fortune."

"He doesn't want any money, Katie. His housing in Brussels is free. He likes the idea of a responsible person being in his apartment, keeping an eye on things, you know. If you're interested. For however long you need it over the next year."

"He's serious, Dad? Really?"

"Completely. He's leaving a week from tomorrow, so you should get in touch with him ASAP if you're interested."

"Oh, my God, of course I'm interested. I've seen nothing but the most depressing places all week. Could you text me his numbers, please?"

"Done."

They chat companionably for a couple of minutes. As soon as she ends the call, she squeals and kicks her heels against the sheets. "Castle Castle Castle Castle! I have a place to live! I can't believe it. An apartment. And it's a block from the subway."

He knows that he's being a little unreasonable, but he's afraid that the rattling and banging that he hears in his head is the moving van driving down Broome Street, about to stop in front of his building. What if she never comes back? What if she loves her independence so much that she wants to keep it? What he wants to do is shout, "YOU ALREADY HAVE A PLACE TO LIVE, BECKETT! IT'S RIGHT HERE." What he does instead is say, "Oh." He's trying, but it's very dispirited. "Oh. That's really good."

"That wouldn't fool a three-year-old, Castle," she says. "You don't think it's good at all."

"I know. I'm sorry. I just don't want you to go."

"It's not for forever, you know."

"Are you sure?"

"I only have the place for a year."

"And then what?"

Beckett gets up on her knees and pivots so that she's straddling his thighs. "That's the point, Castle. I'm going to work really hard on the then. On us. On the future. That's why I'm doing it. Okay?"

"Yeah," he says. He's about as morose as she's ever heard.

"You know that I love you."

"Yeah."

"Since I'm not sure that I'm getting through to you, I'm going to be explicit. If nothing else, you must be feeling it. That I love you. On your thigh. Where I'm sitting."

He's looking at her, but not reacting.

"C'mon, Castle." She waits a beat and then gives him her most seductive smile. "Don't be a wet blanket."

That does it. He laughs, and laughs some more. "Can't have that, Beckett," he says. "A wet sheet maybe, but not a wet blanket."

The following Friday, with very mixed emotions, she packs her things in a corrugated carton from Amazon. It takes two minutes. Castle is horrified.

"Stay right here," he says, as he puts on his coat and walks towards the door. He reappears an hour later with a hand-stitched leather suitcase. "Leaving here with everything in a box is unseemly, Beckett," he says primly.

On Saturday, he drives her and her new suitcase to Sam Harrison's one-bedroom apartment on the Upper West Side.

They don't exactly settle into a routine, because there's nothing routine about their lives. But some nights she stays at the loft with him; some night he stays with her; some nights they're on their own.

Beckett, who once reveled in her solitude, more and more finds that she has too much of it. It's November now, and the nights are longer and chillier. She's missing him and she has no compunction now about saying so. She picks up the phone and texts.

"Hey."

"Hey."

"Wanna come over?"

"Sure. But I thought this was your solo night."

"Changed my mind. Duet."

"Be there in 25."

He gets there in twenty-two. "A personal best," he says proudly. "I was about to get in a cab by the subway entrance when I heard a train coming into the station so I ran down the stairs and just made it."

"Impressive," she says, giving him a kiss. "I hope you didn't wear yourself out."

"Not a chance." He flops down on the sofa, snagging her wrist on the way so that she lands on his lap. "So, a duet, huh?"

"Uh-huh. I'm feeling quite inspired."

"Really? By what?"

"The opera. I was looking out the window before, because you can see a little bit of the balcony at the opera house from here. I like watching people go out there during intermission."

"So what's on tonight?"

"Tristan and Isolde. Wagner." She's leaning her head against his chest. "Very, very, very long. It's like an endurance test for the two lovers."

"This is inspiring you, eh? You gonna sing?"

"Not sure, Castle," she says, pinching him. "But I'm pretty sure you can make me yell as loud as any Wagnerian."

He puts his hands around her waist and stands them both up. "There's a challenge I'm happily accepting. How long is this opera, anyway?"

"Five and a half hours," she purrs.

"Jesus."

And then one Friday night in January he's moping around at home alone when the doorbell rings. Who the hell does that at eleven o'clock? Must be a neighbor, since the doorman didn't ring up. He opens the door. It's Beckett, with her hand-stitched leather suitcase.

"Beckett! This is a surprise."

"Mister Castle?"

"Uh, yes?"

"May I come in?"

"Of course." He waves her in. "May I take your coat? Detective Beckett, is it?"

"Yes, thank you."

It's navy blue wool. He doesn't think that he's seen it before. "May I get you a drink?"

"I don't drink when I'm on duty, Mister Castle." She raises one eyebrow.

"Oh, I see. Well, what can I do for you? May I help you with your suitcase?"

"No, thank you. I'll hold on to it for the moment. I understand that you have an unusual room here. A secret lair, I believe you call it."

"Yes. Yes, I do. Is there a problem?"

"I hope not, Mister Castle. I'll have to ask you to show it to me."

"Certainly. Um, right this way."

They walk into the office, and he's relieved that she can't see his face as he's trying to figure out her game. He activates the door. "Here we are, Detective."

He turns on the lights, and she lifts her suitcase onto the coffee table. "Just as I thought," she says, as she looks around.

"Just as you thought?"

"Yes." She leans over, opens the suitcase and removes a large role of yellow tape. "What is behind the doors of that cabinet, Mister Castle?"

"Oh, that? That's a Murphy bed. It works—"

"I know how it works, Mister Castle. Please open it for me."

"Sure. Of course. Right now." He opens the doors and pushes the button that sends the bed down.

"Stand aside, please."

He does. And then he watches as she attaches the tape to one side of the cabinet, loops it around the bed and finishes by attaching it to the far side of the cabinet. CRIME SCENE. DO NOT CROSS, the tape reads over and over, in large letters.

She puts the roll on one of the shelves and dusts her palms against each other. "There," she says.

"Crime scene, Detective Beckett? This is a crime scene?"

"It certainly is, Mister Castle. I have to ask you to come with me."

"Do I need to call my attorney? Are you charging me with something?"

She picks up her suitcase. "If you'll come with me, please."

"Of course. I always cooperate with the NYPD."

"I'm glad to hear it. I'll follow you out. Please don't try to escape."

"I wouldn't dream of it, Detective."

When they're back in his office, he stops and looks at her. "Over here," she tells him, nodding towards his bedroom door. "Please sit down on the chair."

He does as he's told, and this time she drops her suitcase next to the bed. "Um, Detective? Don't I have the right to know what crime you believe I've committed?"

"You do," she says, and kicks off her shoes. "In that room, that secret lair, you stole my heart."

"I did?"

"You did," she says, as she unzips her pants and steps out of them.

"Are you here to take it back?"

"No, I want you to keep it."

"Am I under arrest?"

She pulls her sweater over her head, lets it fall next to the pants, and shakes out her hair. "Yes, you are. House arrest. Here, with me."

"I see," he says, looking her up and down and taking in the blue silk excuse for underwear that she's wearing. "For how long?"

"Forever. I'm here to stay."

A/N That's it for this story. Thank you all for cheering on something that I thought would be no more than three chapters long.