Author's Note: Who didn't love that scene (from "Always Buy Retail," S1E06, if I remember) when Castle told Kate not to call him Kitten? I mean, come on. The sexual tension! Anyways... I won't bore you at this junction with how my completely strange mind came up with this idea, but if you really want to know, I have an answer.
Setting: I have no idea when this takes place. It really doesn't matter all that much.
Warning: This is 100% silliness. If you're not looking for something slightly ridiculous, and somewhat crack!fic-like, well... Yeah.
A Kitten and a Kitty
"Beckety-Beck-Beck-Beck?" Castle cut in, interrupting Esposito and Ryan's tête-à-tête before the former had the chance to reply.
Both of the Detectives rolled their eyes, but it was Esposito that spoke. "That's taking it too far, Bro."
"Becks," Ryan suggested, starting the game back up.
"K-Becks," Esposito corrected.
With reverence, like the appellation meant something more to him, Castle sighed, "KB."
The other two failed to catch onto Castle's dreamy tone. "Kay," said Ryan.
"Katie," Castle chimed, his head cocked to the side like he was imagining a younger version of the Detective in question, a child version of the woman whose Dad calls her Katie.
Esposito stood from the chair behind his desk, puffed out his chest, squared his shoulders, crossed his arms, and growled, "Kath."
Ryan stood, too, mirroring Espoito's position. He bumped his chest into the Latino's. "Ket."
The spell broke. "Ket? Really? That's all you got?" Esposito uncrossed his arms and scoffed, "Katerrrina," his r's rolled.
Castle chuckled, "Kitty."
"What was that, Kitten?" a familiar female voice purred from behind the men.
Beckett strode over to the huddle from break room and announced her presence, much to Castle's alarm. When he turned to face her, his eyes focused on the steam rising above the mug. She was clutching the coffee at her sternum, her posture erect and demanding power. By the time his line of sight trailed back to her face, she was already walking towards her desk, a cool breeze hitting his skin as she passed by him on her way.
"Uh—I," he stuttered, unprepared for even the possibility of her wrath. He gulped. "Alexis keeps telling me, not so subtly through pictures in texts and Tweets, that she wants a cat."
Her eyebrows raised, her lip twitching with a small grin threatening to develop into a full smile. "A kitten?"
"Yes," he answered much too quickly.
Beckett nodded, a deep hum in her throat. She and Castle both looked at the other two, Beckett's stare commanding, Castle's pleading. Both obliged as Esposito and Ryan quietly returned to their desks and pretended to work.
Just like Castle was pretending to be absorbed by his phone.
Flipping through a file, she commented, "I thought Alexis was allergic to cats. Isn't she, Kitten?"
Castle's head snapped up and he dropped his phone in his lap. His jaw opened and closed a few times before he spoke. "No. She—" He leaned closer to her, his elbow propped on her desk, and whispered, "I thought we agreed you'd never call me that ever again. Ever."
She rolled her chair towards his, bringing her face close enough for their noses to be millimeters from brushing. Her gaze switched back and forth between his eyes, moving left to right, left to right, like the pendulum of a clock. She parted her lips, quickly wet them with a flick of her tongue, and stared at his now agape mouth. He watched as she moved her head slightly to the side, missing the movement of her hand until she was pushing his shoulder back.
"That was before you called me Kitty."