A/N: This is my first attempt at a Castle fanfic. I might be a bit out of character, so I apologize in advance for that. Detective tom demming
***
Castle was an expert in many things: the typical exports of foreign countries, common motives for murder, how to see if someone was lying, and—of course—all things fiction, just to name a few. But losing; now that was completely new concept for him.
He never lost. Ever. Sure, he hit a slump every now and then, or maybe stumbled into a bout of writer's block, but he never lost. It was just unheard of.
Which was why he was so stunned to find himself in this position. Not only had he just lost a game of poker to his daughter, but he was losing his Beckett to another man! Sure, Detective Demming was a nice enough person, and Kate certainly deserved someone that would treat her right and appreciate her, but did the guy have to intrude at work, too?
It has always been just Beckett and him. They'd bounce ideas off each other and banter back and forth, until they somehow managed to come up with the correct scenario for whatever case they were working on. Then they'd use a combination of his knowledge of criminal minds and her training and intuition to figure out who committed the crime and, later on, to catch said person. Their system was slightly dysfunctional, sure. But it worked, and it caught the perpetrators, so why mess with it? What right did this Demming character have to barge into an already laid out plot?
Castle supposed he might, perhaps, be a tiny bit jealous. He and Beckett had been getting along much better lately, and after that scare only a few weeks ago, he was feeling rather…possessive. He'd never felt that way about anyone other than his daughter before, but he figured the clenching in his stomach he experienced every time he saw Demming and Beckett together was a standard reaction, one that anyone would feel in his shoes. After all, she had almost died—twice! And if she had…well, then where would he be?
Maybe that was the thing that scared him most: losing Beckett completely. She'd become such a constant in his life, and he looked forward to seeing her each day. He enjoyed tagging along with her, embarrassing her, and generally annoying her. But, he also liked her witty comebacks, her eternal drive, her perpetual need of caffeine. He loved being able to make her smile, and seeing her in her rare vulnerable moments. He wanted to comfort her, hold her, when something went wrong. The look in her eyes when she was thinking about her mother, that desolate, withdrawn look, almost killed him. He'd happily give his life for her in those moments.
Could he stand it if she left? If he lost the companionship he'd taken for granted? If he no longer got to see the woman he'd begun to rely on so much? No, he wouldn't. She was his muse, the reason he was writing again. But, she was more than that, too. She was his best friend.
Basically, it came down to this: Was anything going on between Castle and Beckett? No. Did he wish there was? He had absolutely no idea. Either way, though, he didn't like Demming moving in on his territory, and he was sure as hell going to do something about it.
Because he was Richard Castle, and he never lost.
***
Okay, that's it. Phew! I needed to write something angsty. I might—possibly—feel the need to write more. Either a continuation or something kind of connected. Or, a completely different take on that line. (I LOVE that line! There's so much you can do with it, and it was acted so beautifully! "I don't like losing." It's just so perfect!)
Anyway, if there are any mistakes, or you have any comments/constructive criticism, please leave a review or private message me! I love all feedback!