AN: So, my brain just loves this universe. This little story will comprise of one-shots, ranging from short to long, that exist in the "By the Light of the Moon" world, so I recommend giving that a read, if you haven't already, before diving (pun not intended) into this. Anyway, enjoy!

Disclaimer: I don't own Castle.

Kate scrunches her nose as she fills in the latest form for yet another case file. It's late afternoon, and the homicide floor is quiet, with the exception of Ryan and Esposito ribbing each other about whatever. She can hear them just fine, but she isn't paying attention to any of the words.

Glancing at the computer clock, she notes it's almost quitting time. Just one more file and then she can go home to Castle and begin their romantic date night. Castle's been, or at least should be, writing all day, but she's sure he's spent some of it prepping for tonight. The mere thought prompts a small smile from her. God, she's such a sap.

"What are you smiling about, Beckett? Writer Boy do something right for once?" Espo teases from across the way.

Rolling her eyes, Kate smirks before returning to her paperwork. "Maybe I just enjoy the silence here."

She hears the scoff as her coworker returns to his desk.

"You two are disgusting," he grumbles as he plops down in his chair. "You've been dating for what? Three months? I thought the honeymoon phase would be over by now."

A snort escapes her lips. She is so not telling Espo that the honeymoon phase never really ends, for her kind at least. "I thought you'd be dating Lanie by now," she snips, which promptly shuts him up as he returns to his own paperwork.

She continues her paperwork for a little while longer, until Ryan interrupts her work flow with a fairly alarming question.

"Did the forecast say it was going to rain today?" he inquires.

"Er, no, why?" she asks, gazing up from her desk, her eyes flicking toward her coworker and he gestures outside. She turns to the window, observing the scene outside and that's when she sees it. Storm clouds. Her stomach sinks at the gray sky forming, and the even blacker clouds she can see approaching.

"Looks like it's gonna storm. Weird, huh," Ryan hums. "So, with that, I'm heading home lest I get caught in the downpour. Besides, it's quitting time anyway."

Ryan grabs his jacket from the back of his chair and heads toward the elevator.

"I think I'm gonna head out too," Esposito states, beginning to shut down his workstation.

Kate purses her lips as she stares at the window, raindrops already forming on the glass. Shit.

"I think I'll stick around for a bit," she says and her coworker gives her a nod before heading out himself.

A soft sigh escapes her as she pulls out her phone. Looks like she's going to be late tonight. Her fingers begin to type out the text to Castle, but in the middle of it, he sends her a message of his own.

Town car on the way. See you in a bit. ;)

As her teeth chew at her lip, her face threatens to break out into a grin as she reads the text. Her partner can be so sweet, when he isn't regaling her with his crazy theories, of course.

After closing down her workstation, she makes her way out, bouncing on her heels as the elevator descends to the lobby. The doors open and sure enough, the town car sits outside, rain beating heavily on the its rooftop. Kate sprints, pushes the lobby doors open, and slides into the car just in time. Some rain hit her, but not enough for a transformation, thankfully.

Hopefully, the rest of the evening is just as smooth.

The town car pulls up to the loft building a few minutes later, and the brunette makes a mad dash to the front, wrenching the door opening and stepping inside. She glances apologetically at a startled Eduardo as she heads up to the loft. As she approaches the apartment, she can smell the delicious meal of...steak, sautéed mushrooms, and potatoes. Mmmm.

"Hey, babe," she greets as she enters the loft, pulling off her jacket and stepping into the kitchen.

"I see your legs are intact," Rick teases, stretching out his arms and pulling her into his embrace before placing a gentle kiss on her lips.

"Thanks for that," she murmurs. "I was going to be late otherwise."

"And we certainly didn't want that," he hums, his chin resting a top her head. "How was your day?"

"Slow, just paperwork. You didn't miss anything. What did you do all day?"

He pulls back, smirking as she raises an eyebrow. "I did do some writing today. In fact, Gina is quite pleased with me." Waggling his eyebrows, he gives her one of his boyish smiles. "Meaning we can enjoy our evening in peace. Which entails a nice home cooked meal, a movie or TV marathon of your choice, a long, hot bath, and some dessert." His voice lowers at the last option, his hands curling around her hips.

"Sounds lovely," she murmurs.

"Now go sit." He gestures toward the island and she obliges, mouth watering as the plate appears in front of her. Good, she's starved!

They enjoy their meal, talking about their day and plans for the week. Touches and gazes are shared as the meal comes to a close. The two clean up before carrying their evening to the couch, flipping through Castle's giant movie and TV collection.

"Mmm, that one," Kate says, curling into her partner who wraps an arm around her. She takes the invite to snuggle closer, her head rubbing against his shoulder in the process.

"Sometimes you remind me of a cat," he comments. "You would look cute as one, probably elegant too." A snort escapes her as a wistful expression appears on his face. "What? You could shrink down, curl up on my chest or sit on my shoulder..."

"Mermaid not enough for you now?" she teases. "You'd rather have something soft and furry to cuddle?"

"No, mermaid is perfectly fine with me."

She turns her head and plants a quick, but passionate kiss on his lips. "Good," she states, clicking the remote for the film to start.

The sit and enjoy the film and each other's company, either snuggling or holding hands as they watch the characters on screen. Once the film draws to a close, Castle rises from the couch to start the water in the tub. Kate follows suit, stripping on the way to the bathroom. It's only the two of them for the night, so she doesn't need to worry about leaving traces of their activities all over the loft.

The tub is big enough that the couple can sit on opposites sides and still move around. However, Castle gets in first, indicating for his partner to sit between his legs. She complies, sliding easily into the porcelain container, her legs morphing into her tail moments later.

"Let me wash you," he murmurs into her ear, and she lets him.

Her tail flicks in delight as he runs the luffa over her skin, gliding over her breasts and torso before moving to her tail. He knows she loves it when he plays with her tail, and this time is no different. His hands gently grasp her fin, massaging along the length, as his lips press against her neck. His ministrations have a pleased hum emitting from her mouth, her body relaxing against him, her tail twitching even more.

Turning her head to gaze at him, she smiles, gently prying the luffa from his hands as his movements slow. "My turn," she purrs, rotating her body so that she's on her stomach facing him, tail up in the air.

Capturing his lips in a languid kiss, she slides the luffa down his neck, his torso, and halts at his stomach. She draws circles on his stomach with the sponge until she slowly descends below his waist, earning a growl from him. Then, without warning, the movement stops and she pulls back, chuckling at his pout.

"Patience," she snickers before reattaching her lips to his skin. Her mouth makes its way down his body until she reaches his stomach. Locking eyes, she winks before dunking her head underwater.

Not needing to come up for air definitely has its perks.