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

How had she not known? Why hadn't she noticed? She's a detective, for God's sake. A highly trained, very experienced, decorated member of the New York City Police Department. She has the highest closure rate in the precinct. Nothing is supposed to escape her, not the tiniest detail of a suspect's body language, not a fleck of misplaced dust at a crime, nothing. En oh tee aitch eye en gee. Nothing.

Oh, yeah, she could make a lot of excuses to herself. She had done that, right away, right after the initial five-minute panic had worn off. She and Castle are in this relationship now. She is besotted. She is crazy in love. She is in a love haze. A sex haze. An everything haze, apparently. Nothing like four years of repressed feelings to turn you into—she leans forward until she's about two inches away from her bedroom mirror—well, this.

She wishes that she could say she knows precisely when it happened, and where it happened, but even in that narrow time frame, the choices are enormous. Here, there. Especially there. But in either, the subset is huge. The when can be narrowed to a couple of days, but still the possibilities are, if not endless, certainly numerous. She turns her head, looks around the room and out through the open door—oh, the door—and blushes.

When she turns the other way, she can see the end of the tub in her bathroom, and she remembers the first time they had sex in it. It was nothing like making love in his Rolls-Royce of a tub, but it was, what? Imaginative. Resourceful. Funny. Romantic. The smaller space was challenging for Castle. "I can always rise to the occasion, Beckett," he said. "And if you happen to be naked on the occasion, I rise incredibly fast."

"What about when I'm all soapy?" she had said, sliding over him. "And slippery?" She slid back. "And wet?"

For a big man, and he is very big—she blushes again, shaking her head at how dopey she's become since Castle, how unembarrassedly silly he makes her—he can move like a jaguar. In the tub that night he had lifted her up and lowered her onto him in one fast and seamless move. He'd stopped when she was tantalizingly impaled on him, not much more than an inch. And then, while sucking hard on one of her breasts, he'd managed to press her down so agonizingly slowly that she had wanted to kill him. Except then she'd never have sex with him again.

In her place alone they've also fucked on the sofa—because, really, fucked is the only word possible for what they did there—made love in the shower and the bed, had sex on the kitchen table, and up against two different doors. And sort of the chair, but they'd slid out of it. Sort of. She blushes again. How can she blush when she's the only person in the room? Come to think if it, she isn't. Not really. Oh, my God. Not really. She runs her palm over her bare stomach. Not really alone.

She's pregnant.

She hadn't planned it. God knows she hadn't planned it, yet here she is. Here she and a little XX or XY are. The best-laid plans of—she gets no further with that thought, except to laugh as she thinks how much Castle would laugh at her choice of words. Best-laid. No kidding. She blushes again. When she had first suspected that she was pregnant, and then taken four tests that confirmed it, she was furious. Angry at herself for her carelessness but angrier at the company that had mislabeled the birth control pills so that she had taken the placebos when she should have been taking the active pills. She had noticed that the color coding was different, but hadn't questioned it. It's amazing that she still had the package but she had, and a visit to the pharmacy and follow-up calls to the manufacturer had proved her right.

A river of fear and anxiety had washed away the anger, and she had flailed in those waters for a day while Castle was at a book fair in Chicago. She had thought that he wasn't coming back until the next morning, but instead he had taken the last flight from O'Hare and surprised her. Really, truly surprised her, since she had been asleep in bed when he let himself in to her apartment, and she had woken with a jolt to a now very familiar hand playing with one of her nipples and a now very familiar pair of lips kissing her just below her ear. She smiles again as she remembers it. Recalls how fear and anxiety had gone right out the window—seriously out, since it had been a pleasantly cool summer night and the window had been open—the instant she had seen him. She knows they'll be back, there will be emotional waves of every sort and magnitude over the next eight months, but she has an almost unknown-to-her feeling of serenity. And happiness. And confidence that this is a good thing. A great and wonderful thing. She and Castle may have been together only since the end of May, but they've been a couple in so many ways for years.

And now she has to tell him. Alexis and Martha are back from Europe, so she doesn't want to spring this on him at at the loft. But it has to be somewhere private, private and personal, which cuts the list down to one: her apartment. She's just about to call him when she stops, her index finger hovering over the screen. She doesn't trust her voice, worries that it will shake even more than her hand is doing now. He'll think something is wrong, when in fact it's right. She thinks. She does. So she texts.

"You and Alexis back from dinner yet? Can you come over?"

Bubble bubble bubble, here comes his immediate reply. "YES! Are you my dessert?"

"Might be."

"Right now?"

"Yup."

"Already out the door. 15."

It was barely 10. He probably gave the cabbie a hundred bucks to floor it.

"You're in a hurry," she says as soon as he's inside.

"Never like to wait for dessert, Beckett," he says after a kiss that could melt a gallon of Rocky Road.

"Uh, about that." Now she's a little nervous after all, and she pulls away from him. "Um." She looks down at her feet. Silence. Continuing if vibrating silence.

He wraps one hand around her chin and tilts it up until she finally lifts her eyes to meet his. "Beckett?" He swallows hard. "Is something wrong?"

"I need to sit down. Over here. There. Sit on the sofa. For a minute." The sofa, the sofa that was one of the Site of Conception possibilities. "I mean, you should sit down." She runs her hand over her face. "Both. We should both sit down."

He reaches for her hand. "What's the matter? Did I do something? I'm sorry, what. Oh, God."

She squeezes his hand. "Nothing's the matter. You didn't do anything. Well, you did. We did. Castle, let's sit." As soon as they do, she gets back up. "Wait, no. Wait. I have to stand for this, okay? But you stay sitting. So in case you faint you'll be on the sofa. Or if I faint you can catch me."

It takes every bit of his reservoir of self-control to keep quiet, but he knows better than to hurry her. Let her say whatever she needs to. It can't really be bad, right? She said she could be dessert, so how badly could he have screwed up? He can't think.

"Castle?"

"Yeah?"

"You all right?"

"Yup. Ready as can be. For, you know, whatever you're standing for, and I'm sitting."

She tucks a strand of hair behind her ear. "You know how incredible it's been lately."

Oh, God, that doesn't sound good. No, that sounds like "but" is going to follow. Still. "Oh, beyond incredible. Beyond."

He smiles his best smile at her, not because he thinks it might help his case, whatever his case is, but because he can't stop himself.

"Everything has been incredible," she says. "The talking, all the making up for lost time, the—"

"Sex." Shit, he hadn't meant to say anything. That just came out of his mouth without permission.

"Yes, sex. Sex. That's kind of what I have to talk about."

"You want to talk about sex, Beckett?" He's really confused now. "I'm happy to talk about sex, even happier to have it. But with you, always happy with both. You know, either one. Talking or doing. Or both."

She's looking at him but she's not looking at him. "Okay, well, you know, we've been having a lot of sex."

"Isn't that good? I thought it was. Great, actually, not good. Fantastic. Like night before last when you had that feather thing and—"

"It was, is. It's just." She'd never thought it possible for someone really to wring their hands, but she realizes that that's what she's doing. "It's. My pills were wrong."

Confusion just went up a few notches. "Your pills?"

"My birth-control pills. The most recent batch was mislabeled. And now I'm pregnant. We're, uh, pregnant."

"We're what?"

"Pregnant." Her voice begins to trail off. "Having a baby." It's so soft now that she's almost inaudible. "Ours."

He jumps off the sofa and engulfs her, hugging her so tightly that it feels as if his arms have come around her twice. Then he's babbling, something like "this is the best thing in the history of the universe," she can't quite decipher it. And then he relaxes his grip to look into her eyes. "It's the greatest news ever, right? Beckett, you're not upset, are you?" Before she can answer, he looks pale. "You want to have a baby, don't you?"

"No, I—"

"No?" He looks shattered.

"No, I don't want to have a baby, Castle, I want to have this baby."

"Really?" He's squeaking. "You do?"

"Yeah, I do. Crazy, right? I mean, we're barely together, and—"

"Barely together, are you kidding? I've been in love with you since our second case."

"No, you just wanted to get in my pants in our second case."

"No, I just wanted to get in your pants on our first case. But I began to fall in love with at the end of our second, when I saw how compassionate you could be, when you were persuading the nanny, Chloe, to put down that knife. By the time we got to the case of the little girl who'd been kidnapped, a couple of months later? I was a goner. Total goner. I wanted to have kids with you from that moment."

"Well, I guess you got your moment then. I'm sorry it took so long. But I know there's a lot to figure out."

"Let's go to bed. Just go to bed, that's all. There's nothing to figure out. Well, okay, there are things, but we'll do that. We excel at figuring things out."

When they've brushed their teeth and gotten into bed, she tells him about the suspicions she'd had, and the pregnancy tests she had taken. Castle draws her onto his chest. "You were mad at the beginning, then."

"Do you blame me, Castle? Are you mad at me?"

"Of course not. But you didn't ever think about—""

She puts two fingers over his mouth. "No, no of course not. I did briefly consider suing the birth-control pill company though."

"Yeah?" He pulls her even closer and chuckles. "I wouldn't have done that."

"You wouldn't?"

"Hell, no. I'm going to write them a thank you note."

"First thing in the morning, Castle," she says, kissing him in the center of his chest.

"First thing, Beckett," he says, and smiles.

A/N I got the idea for this bit of fluff when I heard on the news this morning that 113 women are suing a pharmaceutical company, claiming that a birth-control pill packaging snafu had resulted in scores of unplanned pregnancies.