Title: The Great Water Balloon Fight of 2012

Summary: "I have... 120 water balloons." "Why 120 of them?" Fluffy oneshot.

Disclaimer: I do not own Castle. Sometimes I have dreams, but... no.

Spoilers: Through Season 4 Always.

A/N: This is a fluff fic inspired by a tweet from 'Richard Castle.' I may have strayed for pure fluff but tried to keep conflict minimal. Reviews are always appreciated.

"I have… 120 water balloons," Castle declared as he carried a large plastic bucket full of the fluid ammunition towards the roof.

"Why 120 of them?" Kate asked as she followed behind. Wisely, she had changed into a bathing suit top despite Castle's offer to lend her a white t-shirt (which he said with a knowing grin and a wink).

"They come 10 to a package. I bought 13 packages."

"Thirteen packages?" she said. "Wouldn't that be 130 water balloons?"

"A few broke."

"A few? You broke ten!"

"No, I only broke three. But 127 balloons just isn't a good, round number. So I threw out the other seven to make it an even 120 balloons."

It occurred to her that 120 was not only an even number, but one divisible by three. Castle continued up the stairs, and she held open the door for him once they reached the roof. "So, if you and Alexis do a big water balloon fight every year, where is she?" Kate asked.

"Actually, Alexis is spending the day at a friend's house. Mother is likewise otherwise engaged, not that she would be interested in throwing around pieces of plastic full of water. So that leaves you, my dear Kate, to help me carry on the tradition of the annual summer water balloon fight."

"Just you and me?" she queried. "Wouldn't you rather wait for Alexis to get home?"

While she and Castle's daughter had been getting along fairly well over the prior few weeks, Kate was still hesitant about breaching the bounds of the father-daughter relationship the two shared. She took special care to make sure he and Alexis had plenty of time together considering it would be Alexis' last summer before college.

"Oh, not to worry. I have another 13 bags of balloons downstairs. She and I will be having a balloon fight, even if she doesn't know it when until I lure her up to the roof."

Kate smiled. "You do this every year. You don't think she'll suspect something?"

"Oh, every year I think of a new tactic," Castle explained. "Although, when she was twelve, she made me promise not to begin the fight inside... incidentally, that was the summer I sprained my ankle."

Picturing him racing through the kitchen and then slipping on the shattered remains of a broken water balloon, Kate could not help but laugh.

As he set the bucket of full balloons down on the ground, Kate took the opportunity to look around the roof. The area was well utilized to provide a little bit of green in the city's otherwise urban landscape. While there was no grass, the typical concrete and gravel flooring had been replaced with wood decking and stepping stones. The path ran through and around a multitude of pots of all shapes, sizes, and colors. Some were small and held only a single bulb or flower. Others were large and elaborate, containing small shade trees, elephant ears, and other leafy green bushes. Off to one side was a small, shaded area with a couple of chairs under a gazebo-style wooden canopy.

The center of the roof contained a clear area where Castle had placed the bucket. Out of the corner of her eye, Kate noticed him removing one of the filled balloons. But as she turned to ask about the rules of this summer sport, he simply hauled back and let the balloon fly in her direction.

But rather than explode upon impact, the balloon bounced off her body just as she had the wherewithal to react, and it lurched back to the ground in a wobbly arc. Hitting the wood deck, the balloon bounced a few more times before finally popping a few feet away from Kate.

Barely taking in Castle's disappointed frown, she dove for the bucket of balloons. The game was on. And clearly, no rules.

Either by luck or kismet or skill, Kate escaped the first few rounds relatively dry. While most of Castle's throws had hit her, few of them actually burst upon impact. While she had gotten a bit damp from close proximity shots, she still remained unscathed.

Castle, on the other hand, was close to soaking wet, all of her shots on him having exploded perfectly.

"This isn't fair!" he complained after yet another of his balloons bounced harmlessly off of her and landed neatly in a nearby potted plant. "It's like you're made of rubber or something. They hit you but won't break."

Retrieving the intact balloon from the plant, Kate lobbed it back at him. It dutifully burst on impact with his chest.

"That's what you get for starting with a sneak attack," she told him.

They were both out of ammunition and each approached the bucket with caution as they eyed the other suspiciously. Then Castle made a run for it.

Prompted by his sudden action, Kate also sprang forward. They reached the bucket at the same time, both reaching in anxious hands to grab balloons. But instead of retreating to aim and throw one at her, Castle simply grabbed two and, leaning forward, smashed them over the top of Kate's head.

Momentarily shocked by the water, freezing cold in contrast to the warm air on the roof, Kate gaped at him, stunned by his tactic. A few seconds later, she recovered enough to yell, "Castle!"

"Oh crap," he mumbled, grapping a few more balloons before running in the opposite direction.

First one, then two, then three balloons hit him in the back as he ran, Kate simply grabbing them directly from the bucket to reload. But once he was out of range and dodged behind a large potted tree, she had to abandon the open position at the bucket in favor of better cover.

But as Kate ducked to the side of the gazebo, something suddenly occurred to her. Despite the trees and the plants and the calm, serene nature of the garden, it was still a roof they were on. And while they were using water balloons instead of guns, she was still hunting and being hunted.

Suddenly, the flora and fauna were a little too confining, like walls closing in. The sun overhead was too hot, beating down unmercifully as it reflected off the windows of neighboring buildings. The gleaming lights were blinding, like the shine on gunmetal or the reflection off the scope of a rifle.

Sucking in breaths of air with desperate haste, Kate tried to calm her racing heart and make everything stop spinning out of control. She and Dr. Burke had discussed these attacks months ago when she first admitted to suffering from post traumatic stress disorder. They had all but disappeared since the beginning of the summer and her resignation from the force. But something about the situation took her back to that day with Cole Maddox throwing her around like she was nothing more than a child, and then her hanging by her fingertips from the edge of the roof. Thoughts of the man who had shot her tended to bring back that day at Montgomery's funeral. The memory made her chest burn as she struggled to get in enough oxygen and she imagined that she could feel her scar pulling.

And then Castle was there, kneeling on the ground in front of her. His face betrayed concern and belatedly, she realized that he must have been calling her name. "Kate," he said again, bringing the world back into focus.

"I'm okay," she managed. He had reached out a hand instinctively but stopped short of actually touching her. In an attempt to reassure him, she took his hand and held it tightly in hers.

"I'm so sorry," he said, the knowledge of what had set her off reflected as guilt in his eyes. "The roof and the balloon fight... I wasn't thinking."

"No, Castle, it's fine. I'm fine. Just needed a little breather."

His brow furrowed as he listened to her try to brush off the PTSD attack. He had not been with her through too many, although he had woken her up from a several nightmares.

"Don't do that," he said. "Don't act like it's nothing."

"I don't like talking about it, Castle."

More gently, he responded, "You don't have to. Just don't try to play it off. I'm here for you. You don't have to pretend with me."

Kate nodded, acknowledging his words. Being in a relationship with Castle was certainly taking some getting used to. Unlike her past boyfriends, he did not let her hide from things or hide things from him. When she tried to run or cover something up, he confronted her with loving devotion. At every turn, he encouraged her to open herself up a little more. And little by little, she was doing just that.

The vulnerability she felt with him was almost as scary as feeling exposed on that rooftop. Her one consolation was that she knew he would never hurt her - never intentionally, anyway.

"Why don't we take a break?" Castle suggested as he helped her to stand. Looking down, Kate realized that she had broken the water balloons she held on herself, completely soaking her shorts. The cool water felt good on her skin.

She let him lead her under the cover of the gazebo. Inside, she realized that it was made of wood rather than metal or plastic, and there was even an electric ceiling fan creating a slow, lazy breeze. Castle left her alone for a moment as he ventured back downstairs to get her a bottle of water.

Kate realized that she was alone on the roof, the only sounds coming from traffic on the street below, the kind of noise which faded into the background for most New Yorkers. On a whim, she stood up, feeling less shaky than she had a few moments earlier. She walked determinedly towards the roof's edge, glad that a small three foot stone wall kept any possibility of tumbling over to a minimum.

As she approached, Kate could feel her anxiety level growing. But she simply took a deep breath and kept going. She would conquer this fear.

Castle's roof was not quite as high as the one she had dangled off of that fateful day just a few weeks earlier, but it was still high enough that she had no hope of surviving the drop. Shuddering, she stepped away from the edge. Kate had walked away from that part of her life, from the danger that obsession could bring. And she still had no wish to go back to it.

She heard footsteps behind her and turned instinctively. Castle approached with a bottle of water in one hand. He grinned at her, that genuine, I'm-so-happy-you're-here look he had been giving her since she arrived wet and wanting on his doorstep. She could not help but smile back at him.

"So, ready for round two?" he asked.

She could tell from his tone that he was not ignoring her earlier episode or brushing it off like he had accused her of doing. Rather, he was not dwelling and instead giving her the opportunity to conquer it.

"Absolutely," Kate said.

"Okay, but this time I'm not going easy on you. You will be getting the full-on Rick Castle Water Balloon Fight treatment."

Laughing, she followed him back to the bucket of full balloons. "If you can get them to actually break when they hit me."

"That's really weird," he commented. "Did you do something to the balloons when I wasn't looking?"

She snorted. "Like what?"

"I don't know. Maybe you bewitched them."

As he spoke, he reached out a finger to snag one of the loops of her shorts.

"Bewitched them?" Kate repeated. "Do I look like Samantha Stevens to you?"

His other hand snagged a loop on the other side and Castle used the strips of fabric to pull her towards him. She moved willingly as he tugged, amused by the tactic. As he pulled their hips flush against each other, she wrapped her arms around his neck.

"I don't know," he said casually. "I'd have to see you twitch your nose."

In response, Kate attempted a Bewitched-style nose twitch but could only succeed in scrunching her nose. They both laughed at the resulting face she made.

"You're adorable," Castle told her.

"Says the man who still has water balloon fights every summer."

By way of response, he simply pressed his lips to hers, gentle at first, content to just enjoy the feel of her and the softness of her skin.

Kate deepened the kiss, wanting that contact and intimacy. She loved the way Castle kissed, always surprising her with his tenderness and his eagerness to discover everything she enjoyed. His kisses not only conveyed sensuality and yearning, but also deep love and affection.

They both startled a moment later as something impacted them and immediately doused them in a snap of cold water. Kate could not quite contain her scream at the sudden drenching any more than Castle could. Breaking apart, they looked in the direction the water missile had come from.

There, standing in the doorway to the stairwell, was Alexis. And she was armed with her own water balloons.

"Alexis," Castle said in confusion. "I thought you were at your friend's house."

"And miss the great Summer Water Balloon Fight of 2012?" the young woman asked. "No way!"

Seconds later, water balloons were flying all over the roof in different directions as each of the three combatants attempted to hit the other two. As she ran and ducked, giggled and squealed, threw balloons and got hit by them, Kate quickly found the memory of her last roof experience replaced by a much brighter one.