Disclaimer: I don't own Castle and don't profit from writing these stories (except for my own amusement).

FLAGS ON PLAYS

He and Kate quickly settle into a routine. He's gotten used to waking up at her impossibly early hour. He keeps a work week's supply of shirts and ties in her closet, right next to the four or five blouses she has in the same style but different colors (they were on sale was her answer when he asked about it). His bar of soap sits next to her cherry body wash in her shower caddy (his partner had given him a strange look on the first and last morning he used it). They share a cab to work (she always insists on paying her half of the fare). He takes his coffee breaks in the Homicide break room and eats his lunch with her in one of the Homicide meeting rooms. At the end of the day, he goes upstairs to pick her up and they take a cab back to her place again. They either order in or, if they're feeling adventurous, they try to whip something up from whatever is still edible in Kate's fridge. On weekends they take walks in the park (which she likes) and go grocery shopping (which she doesn't). On their nights off he'll sit on one end of her couch drinking a beer and watching whatever sports event happens to be on, while she'll be curled up against him with one of her library books and a glass of wine.

It's nice, he thinks, having someone to go home to, especially when it's someone like Kate. Kate is smart and funny and beautiful and just plain amazing, and he can't help wondering whether he's going to find out that there's some sort of catch.


She's set boundaries, of course. She's spelled out clearly that they're not supposed to talk about this thing between them to their colleagues. True to his word, he doesn't, although he suspects Esposito and Ryan already know. Esposito looks at him appraisingly, as if he's trying to decide whom he should side with should things fall apart. Ryan watches him with barely concealed amusement, as if he's watching some incredibly ridiculous chick flick he's been dragged to by his girlfriend. (As it turns out, Kate doesn't like chick flicks. She does, however, like con movies.)

Beyond that rule, Kate makes her own efforts to hide the fact that they're seeing each other. In the mornings she'll get out of the cab several blocks before they get to the precinct. She always claims that she needs the exercise or she wants to buy some breakfast from the bakery down the street, but he knows she doesn't want to be caught walking into work with him. When he comes upstairs in the evenings, she'll stall until it looks like there's no one watching them leave together. She won't eat off his plate at lunch and she'll step away when he stands too close when they're making coffee. Her need for privacy is one of the most frustrating things about their relationship.

But it's not the most frustrating thing. That honor belongs solely to one Richard Castle.

What was the guy's problem, anyway? Apparently, no flag on the play had not excluded the possibility of being tackled at every move. Constantly trying to one-up him on the Wilder case, making cracks about how Robbery detectives weren't qualified to investigate homicides, and basically just acting like an overgrown ten-year-old around Kate…

As any good detective should, he's done his research. He's found out from Esposito that Castle's been around for more than fourteen months, except for some sort of break during summer (he wishes fervently that there will be another extended vacation this year). He's read the blurb in the eligible bachelor article in the Ledger (he wonders whether Kate saw it, and wonders what happened to Castle if she did). He's also looked at the plot synopsis of Heat Wave on Wikipedia. He never asks, but he wonders if Kate has read Heat Wave. He guesses she probably has, and not the Wikipedia version either; it's dedicated to her and all my friends at the 12th, after all. Demming guesses that he would not be considered a friend at the 12th.

The worst part is that he can't create a proper plan of attack without knowing his rival's motivations, and truth be told, he can't figure out what Castle's intentions toward Kate are. Was he just a friend with an overactive imagination and a pathological need for her undivided attention? Did he see her as some sort of conquest? Was he in love with her?

Maybe it doesn't matter what Castle wants, Demming decides. He just wants Castle to go away. Which is why on the first night of the Wilder case, he steps between the two of them and says you ready? just loud enough for Castle to hear.

He expects Castle to get the hint and back off. But no. The man probes further, forcing Kate to awkwardly stammer out some excuse about sharing a cab.

There's an icy silence as they ride the elevator downstairs, as they wait on the curb, as they ride back to her place. He wants to ask her what the big fuss is about; he hasn't technically broken any rules; after all, Castle isn't one of her coworkers, just a guy who's following them around. But if he's learned one thing about women, it's that you never try to justify your actions when they're angry with you. Ever.

When they reach their destination, Kate gets out first and doesn't look too surprised when he doesn't follow. "Night," she says curtly, tossing her half of the fare onto the seat next to him.

"Night," he replies.

His initial plan is to wait until tomorrow to see if she's calmed down, but as soon as he climbs into bed he sees one of her books next to him, and the next thing he knows, he's reaching for the phone.

"Hey," Kate says, when she picks up the other line. Her voice is neutral, neither bitter nor pleased to hear him.

"I'm sorry if I embarrassed you," is the first thing out of his mouth.

She sighs. "At least it wasn't Montgomery or the guys," she mumbles. She says nothing to indicate that she's accepted his half-apology.

"I know that wasn't how you wanted Castle to find out about us," he adds softly.

There's a long pause before she says, "He already knew."

"How do you know?"

"He called you my boyfriend."

He's taken aback by that response; he'd thought that being her boyfriend was a given. Now he has to know. "Well, am I?"

She doesn't answer, and he mentally slaps himself for being so pushy when she's cross with him. There's another awkward pause before she says, "It's late. We've got a long day tomorrow."

"Yeah. Okay. See you."

"Night."


The next morning he comes in, armed with coffee and a blueberry muffin for Kate. She's not there yet, but Castle is.

"Good morning," Demming says, as politely as he can manage.

Castle doesn't respond in kind but instead asks, "What's in the bag?"

"Breakfast for Beckett," he replies.

Without asking, Castle reaches for the bag and peeks in. "She doesn't like blueberry muffins," he says.

"Okay, what does she like, then?"

"Bearclaws, of course," Castle says, as if speaking to a child. He turns his attention to the cup of coffee. "Is this sugar-free?" he wants to know.

Demming feels like he's in Spanish 205 again, being quizzed on verb conjugation in front of the whole class. "What? Sugar-free? She doesn't need to be on a diet!"

"No," Castle explains, "but if she has too much sugar, she'll crash in the middle of the morning and be cranky for the rest of the day."

Demming is starting to get a little cranky, and it has nothing to do with the amount of sugar in his coffee.

When Kate finally arrives, she smiles her thanks at him as she picks up his peace offering, but she sets it down after a single bite. Castle wolfs the rest of the muffin down with a smug smile in his direction. Kate gets a look on her face like she's about to give Castle a lecture but doesn't.

At the end of the day, Demming doesn't dare follow Kate when she says her goodbyes and leaves the room. Instead, he spends an awkward fifteen minutes pretending to read the file and feeling Castle's eyes on his head, until Castle breaks the silence and offers to share a cab with him. He's not sure if it's a jab or a ploy to make sure he doesn't go to Kate's, decides it's a little bit of both, and takes his own cab home.


When the case is finally wrapped up, he finds Kate in the back room processing the charges. He can't help feeling proud; Castle might know her favorite breakfast, but only a detective would know exactly where a detective would be when the crime was solved.

"Can I have a minute of your time?" he asks, and she follows him into the hall and raises her eyes to look at him. He knows exactly what he needs to say to get back into her good graces, and he knows that she's worth swallowing his pride for a moment.

"I really want to apologize for the other night," he tells her. "You've worked very hard to earn everyone's respect, and I'll do everything I can not to compromise that."

The expression on her face softens. "Thank you," she says with a nod.

He continues, "I know I acted like a kid. This is no excuse, but the way Castle acted around you got me a little jealous and I overreacted."

"Don't worry, it's perfectly normal behavior for him. He goes after anything that moves."

She's not joking or playful when she says it; he can almost taste the unusually sharp sting in her tone. Carefully, he steers back to the task of making up. Tentatively reaching out his hand, he says quietly, "So, we're good?"

Kate's fingers meet his halfway. Before he can register what's happening, to his complete surprise, she's leaning in and kissing him. Breaking all of her own rules, right there in the middle of the hallway, where Esposito or Ryan or even her boss might see them. It's completely out of character, he thinks, for this reserved, no-nonsense woman he's come to know. He can only conclude that Kate must be one of those people who go out of their way to forgive those who are humble enough to give a proper apology.