A/N: It's been a while, huh? Sorry I've been MIA for so long, guys. I just needed to take a breather and today I realised that I hadn't written anything in months. And I missed it. I know I need to work on my other stories, but those need a little brainstorming first. This one is just to get my writing juices flowing again. I don't know how long it will be, but it won't be long. Just a little something to distract myself and get into the Castle mindframe.

Hope you guys like it. I might be a little rusty.

Disclaimer: Castle is not mine.

Through The Looking Glass

"Daddy?"

He heard his daughter's voice as if it was coming from a great distance. The foggy sleep state he currently found himself in felt like a heavy blanket pinning him down to the bed and he couldn't find the strength to move.

"Daddy!"

The young voice sounded entirely too bossy to belong to a 9-year-old. He knew Alexis was shaking his shoulder, but his head felt like it was about to explode if he moved a single inch. He had known that drinking so much the night before was a bad idea, but he was going through his second divorce in less than ten years, so one night of drinking himself into oblivion was okay in his book. And he had only allowed himself to wallow in his self-pity because his little girl wasn't home.

So what was she doing here now? Wasn't he supposed to go pick her up somewhere?

"Daddy, wake up!"

He cracked one eye open with difficulty, the sun shining through the window making his headache kick up a notch. Sure enough, there was his precious red head princess. She smiled happily when he finally managed to focus his attention on her and leaned down to kiss his cheek.

"Hi, pumpkin." He croaked out, closing his eyes when it felt like a sledgehammer was knocking down every single wall inside his skull. "Weren't you supposed to spend the weekend with your mom?"

"She had an audition or something like that. Dropped me off a few minutes ago." The young girl explained, rolling her eyes.

He sighed and tried to sit up slowly. Meredith really was not cut out to be a mother. It wasn't the first time and it most definitely wouldn't be the last. At least Alexis hadn't come back home crying this time. It seemed that she understood better now that she was older. Her mom was more like the crazy aunt that stopped by once in a while. He was the only parent in this family, really.

"You okay?" He tucked a strand of her hair behind her ear and pulled her down to lie next to him.

"Yeah. You know how mom is, dad. I don't take it personally." She sighed and he knew that it was not okay, but Alexis wouldn't allow herself to dwell on it. "I was bored, anyway. And I missed you." She said with a small smile, turning around to face him.

"Missed you too, sweetheart." He smiled and kissed her forehead. "What time is it?" He rubbed his eyes sleepily, hoping this godforsaken hangover wouldn't last too long.

"A little over ten. Maybe we could go for a walk? It's not so cold anymore." She suggested eagerly and he chuckled. "Oh, maybe we could go to that bookstore we saw the other day!"

"Sure, pumpkin. As long as you give me a few minutes to wake up properly and take a shower."

"A shower is probably a good idea, daddy. You smell." She wrinkled her nose teasingly and he gasped in mock surprise. "No tickling, no tickling! I take it back! I take it back!" She pleaded and he winced at the sound.

Alexis jumped out of his bed with a speed that actually surprised him and was across the room and through the door in a flash. He sat up and stretched his arms up, groaning when the movement made his headache worse.

God, where was the damn aspirin?

Rick closed the door behind him, shaking his head at his daughter's excitement to be visiting a new bookstore. If there was ever any doubt that she was his kid, her love for books definitely settled the matter in his favor. He called after her that he would be in the mystery session – he had to check out the competition after all – and heard her positive reply back.

Alexis had a routine whenever she came to a bookstore. She would browse for a while, pick a few titles and then settle down somewhere to read the one that interested her the most. It never changed. He would usually give her about an hour before telling her they had to go. She would plead with him to stay just a little longer and they would end up staying another hour. It was infallible. Every single time.

So imagine his surprise when he didn't find her reading a book in a quiet corner an hour later, but talking animatedly with a young woman instead. She was clutching the fourth book of the Harry Potter series in one hand and gesticulating excitedly with the other.

"You're going to love it. It's so good. The best one yet!" She said brilliantly and the woman smiled, making Rick pay closer attention to her.

She was gorgeous. Like, seriously, drop dead gorgeous. Wow.

Swallowing nervously, he made his way to them, trying to think of something clever to say. He was usually pretty smooth when it came to the ladies, but since his recent (and pretty damn ugly) divorce just six months before, he hadn't dated anyone. In fact, he hadn't even tried to meet anyone new.

"She's right, you know. This is the best one yet." He said, leaning against one of the bookcases, feeling like kicking himself. That was the best he could come up with? He was seriously off his game.

"Daddy, hi! I was just telling Kate how awesome The Goblet of Fire is. She hasn't read it yet. Which is good, you know, because you won't have to wait long for the next one now." She added, turning back to the woman. "It's supposed to come out in the summer."

The young woman looked up at him and her eyes widened for a moment, surprise registering clearly on her face. He cocked his head to the side, examining her for a second and wondered if she knew who he was. But the surprise in her eyes was gone in a matter of seconds and she offered him a small smile.

"You won't regret it… Kate, was it?" He offered his hand for her to shake and she did, her warm palm sending a surge of something like an electric shock through his veins.

"Kate Beckett, yes." She said with a smile and he reluctantly let her hand go.

Where were these thoughts even coming from? He sounded like a crazy stalker in his own head.

"Rick Castle. It's really nice to meet you." He said and looked at his daughter for a second, who was standing next to a small table, counting down the pile of books she had selected.

"You too, Mr. Castle. It's an honor, really. I love your books." Kate said shyly and he grinned happily.

"Thank you very much." He said warmly and delighted in the way her neck flushed in embarrassment. "So, a Harry Potter fan, huh?" He lifted an eyebrow teasingly to try to keep her talking. She shrugged with a small smile.

"Got sucked in, what can I say? Just haven't had time to read this one yet." She showed him her copy of The Goblet of Fire. "Glad I had Alexis here to tell me all about it." She nudged the girl playfully and his daughter nodded happily.

"There is this one part that is so funny that-" She started, but Rick quickly swoop in and covered her mouth with his hand.

"Whoa, Pumpkin, spoiler alert. Have I taught you nothing?" He joked and Kate chuckled. She looked even better when she was laughing.

"Right, sorry. You have to read it fast, though. Then let me know what you thought of it." Alexis said eagerly and Kate nodded.

"Sure. But I can't make any promises about how fast I'll be able to read it. I don't have a lot of free time with my job and all."

"What do you do?" He blurted out curiously before his brain could process it. She looked young, maybe in her mid-twenties. He could picture her as a lawyer maybe, just starting out with her career.

"Oh, I'm a police officer with the NYPD." She replied and he could feel her gaze on him, as if expecting a reaction.

"No way, really? That is so cool." He said, looking at her surprised – and a little bit in awe, if he was being honest with himself. "And totally not what I would've guessed."

"Do you catch bad guys, Kate? Can I still call you Kate if you're a police officer?" Alexis asked curiously and she nodded.

"Yes, I do. And of course you can call me Kate. I'm not on duty right now."

"That is so awesome." Alexis looked up at the tall woman in awe. "Hey, we're having lunch soon. Maybe you'd like to come with us?" She asked hopefully and Rick felt the woman's gaze shift to him.

"Oh, honey, thanks for inviting me, but I'm sure you and your dad have plans already." She excused herself, but Rick found himself shaking his head and touching her arm for a moment.

"Actually, you're welcome to come with us, Kate." He reassured her and she bit her lip. "I mean, a beautiful woman who is a NYPD officer and also a Harry Potter fan? That's not someone we meet every day, right, Alexis?" He turned to his daughter, nudging her side. He didn't want it to seem like he was already coming on to her. It didn't sound like he was, did it?

"Absolutely not." The young girl said seriously. Kate chuckled and shook her head, amused. "It's going to be fun, Kate. We're going to Alice's Tea Cup. Come on, please?"

"Is that a restaurant?" Kate asked curiously as they started to head down to the cashier to pay for the books.

"Yeah and everything in it is from Alice in Wonderland. It's the coolest place ever!" Alexis explained excitedly while Rick paid for her books.

He had never seen his daughter so taken with someone she didn't know before and wondered what it was about Kate that had stricken a chord with Alexis so quickly. The redhead was usually outgoing, but she tended to be a little shy around people she didn't know. He looked at Kate again while they waited for her to pay for her book and found himself intrigued.

She was ridiculously gorgeous, that much was a fact. But there was something about her, he couldn't quite put his finger on what exactly, that made her stand out even more. He watched as her thumb caressed the cover of the book gently, and was startled to find sadness in her eyes for a moment. What was that about, he wondered.

"Are you sure this is okay?" Her voice pulled him out of his thoughts and he found her standing in front of him, looking unsure. "I mean, you don't have to…"

"Of course it's okay, Kate. I wouldn't have invited you if it wasn't." He offered a small smile and felt his stomach flip when she smiled back.

Good lord, he thought as they stepped out onto the sidewalk. Who was this woman?

A/N: Thoughts? Should I continue?