Author's Note: I find myself in the temporary lull between college and career, so naturally I've started re-watching Castle from the beginning. Here's another installment in my Encountering Heat one-shot series. I took a couple very minor liberties with 2x17, but I don't think you'll mind. Read, enjoy, and review!

Encountering Heat

The Heat of the Chase

Kate found it difficult to sleep knowing that Castle was in the next room. She considered her apartment to be a sacred, intimate place and having him there should have felt like a breach of personal space.

Should have. But it didn't.

She was annoyed with herself for feeling comfort from his presence. A delusional serial killer was gunning for her and there Castle was, sleeping in her living room to make sure that nothing would happen to her. Never mind that he wasn't armed.

Her body was exhausted, but her mind wouldn't rest. The case, the feds, and the Nikki Heat angle all crowded her thoughts. And Castle was sleeping on her couch. She padded softly out of her bedroom around 3 a.m., admitting defeat in the battle for sleep. She stole quietly through the living room and felt her way through her dark kitchen. She took out a bowl, spoon, and cereal and set them on the counter silently. She fingered the refrigerator handle, bracing herself for the light when she pulled it open. She squinted inside and met with disappointment. No milk!

A grumbling sigh buzzed through her lips, but she poured a bowl of cereal anyway. The clink of the cereal against the bowl unnerved her and she turned her head over her shoulder, afraid she might have woken Castle. There was just enough ambient light in the living room that she could make out his sleeping form. His chest was rising and falling steadily.

She left the kitchen and passed by him, lingering for just a moment. He was, at times, obnoxious, childish, and unruly, but she appreciated his constant friendship far more than he knew. Impulsively, Kate set her bowl down on the coffee table and reached slowly for the throw draped across the back of the couch. Oh-so-carefully, she unfolded it and laid it gently over him. She held her breath, praying he wouldn't stir. He didn't. She stepped quickly back, satisfied. She picked up her bowl and the wine glasses caught her eye. He had poured one for her earlier, but she had declined, insisting that she needed to go to bed. It still sat there, taunting her. She could tell that he had only taken a sip or two from his own. She caught her bottom lip between her teeth, pondering. Maybe a few sips would help her sleep. She grabbed the fullest glass.

Kate never could fully explain why she did the next thing.

Instead of returning to her bedroom with her unsavory midnight snack, she perched on the back of the couch, crossing her legs Indian-style. Her back was facing Castle, but she found that the proximity to him helped calm her thoughts. She had a spoon in one hand and a glass of wine in the other. Her cereal bowl rested precariously on an ankle. The flavor pairings weren't optimal, but she didn't care. She sat listening to Castle's rhythmic breathing and the ticking of a clock on her bookshelf. Pale moonlight and glowing streetlights gave the room a tranquil ambience. Her cheeks tingled even as her eyes began to droop. Was that the wine working its magic already?

"Am I having an out of body experience," a thick, sleepy voice came from behind her, "or are you sitting on the back of your couch with Apple Jacks and wine at…" his voice trailed off as he squinted to read his watch. "Three-thirty in the morning?"

"Go back to sleep, Castle." She tried to sound brusque, but her tone was too soft. "I'm sorry I woke you."

He rubbed his eyes, sitting up. "You're like a freaking cat right now. What are you doing there, anyway? Plotting my murder?"

"Wouldn't you like to know?" She smiled slyly. She swung her legs over the couch, sliding down into a cushion opposite him. They were nowhere near touching, but the air felt charged. She knew he was watching her intently. She ran the tip of her index finger around and around the rim of her glass.

"I couldn't sleep," she said at length.

"The case?"

"Yeah."

He pressed the bridge of his nose between thumb and forefinger. "If it wasn't for Nikki Heat—"

"It's not your fault, Castle." She cut him off. "Sometimes a psychopath is just a psychopath."

"Still…" The tone of his voice held an unspoken apology.

"I know." She paused a beat. "You were right about this wine. It's really good."

"Oh, I know," he grinned, reaching for his own abandoned glass. "And it's good for what ails you."

"I thought it might help me sleep," she admitted, nodding.

"Verdict?" He tried to gauge her.

"Getting there."

They sat in the dark, sharing a companionable silence. He picked at the edge of the blanket she'd covered him with. He didn't say anything about it, but she could see a soft smile playing around the corners of his mouth.

"If you need me to sit up with you and make small talk all night," he began earnestly, "I will. It might help get your mind off of things."

"Thanks, Castle." She smiled genuinely and was tempted by the offer, but the deep shadows under his eyes dissuaded her. "I think I'll make it on my own." She tapped her empty glass with a slender finger. "Worked like a charm."

She stood and stretched, yawning involuntarily as she set her glass down. "Good night, Castle," she said, stepping toward her bedroom. "Thanks for…" Her voice trailed off, words failing.

He understood. "Any time, Detective Beckett. Good night."

He watched her slim form disappear into darkness and he drained the rest of the liquid from his glass, muttering to himself. "Dear God, that woman."

They had just shared a bizarre interlude, one that, in the morning, seemed like just a hazy dream to them both. Neither of them mentioned then or any time after. But as she poured a cup of coffee and he stood at the stove, he thought he saw a coy little smile flick across her face. He remembered something she'd said once, teasing him.

Maybe there's a little more Nikki Heat in me than you think.

He was a definite goner.