Ringtone

She hadn't noticed him playing with her phone until they were already back at the precinct. She snatched it out of his hands as soon as she saw him with it. "What do you think you're doing?" She snapped at him, checking her Facebook and Twitter to see if he had posted something embarrassing.

He feigned innocence. "Nothing, Detective. Just seeing your high score on Flappy Bird." She double tapped the home button and saw that for once he was telling the truth, and Flappy Bird was the last notification he had opened. She rolled her eyes at him and shoved the phone in her pocket. "I deleted it from my phone, and I just wanted to have some fun. No worries, I didn't beat you." He teased.

She shook her head and got out of the car. "You know, I haven't played that game in ages, I should get rid of it."

"No!" He shouted at her, pleading. "It's fun! And once you delete it you can't get it back. Don't do it!"

She rolled her eyes at him. "Fine, I'll keep it on there for you, but don't take my phone without asking to play, deal?"

His triumphant grin stretched across his face, and she found herself fighting to keep her serious expression. "Deal," he agreed. They walked together into the precinct, and he sat in his chair, watching her from behind as she added things to the murder board while she pretended not to notice him staring.

"What did you two find out?" Esposito's voice shook them from their moment, and Kate stood up straight.

"Not much." She answered truthfully. "Liz and Hannah alibied each other out, they were both out of state at a Bruno Mars concert." She pointed to the pictures of the younger women that she had placed under the heading 'of interest'. "Did you find anything interesting in the victim's financials?"

"Yeah, actually." Ryan took the files from Esposito's hands, and passed them to Kate. "There was a large cash withdrawal four days before time of death, but sweeps of the house didn't show any money laying around, and he didn't have it on his person." Kate glanced at their highlighted sections, and read their notes in the margins, preparing to write it all down on the board.

"That, and his mother says he hasn't really purchased anything of value over the last few days, so we haven't really been able to follow the trail." Esposito added.

Kate ran her fingers through her hair in frustration. "Okay. Well we need to do some digging. Gates has been on our asses about this case for the last three days and we're no closer to solving it."

"We're trying." Ryan affirmed.

As if on cue, Gates stood up in her office and started walking towards them. She had been watching them converse, and probably thought they were closer to a break than they actually were. As she got within earshot, Kate's phone began to vibrate in her pocket. But it wasn't her normal, work appropriate ringtone. No, instead, Oh Fortuna came blaring from her pocket. She raced to turn it off, but was clumsy in her confusion. She managed to see Castle's name appear on her screen before she turned it off. She glared in his direction, becoming angrier as she saw the impish grin on his face. And the boys weren't helping either, each physically holding back their laughter with their hands covering their mouths.

"That's a new one, detective." Gates started, calmly.

"I'm sorry, sir, I don't know when that happened."

Gates raised an eyebrow and nodded. "Well, please assure me that it won't happen again."

Kate felt the heat come rushing to her cheeks as she was reprimanded. "Of course. Let me get you caught up." She managed to maintain her dignity while she caught her boss up on the case, assuring her that she would work her hardest to find a break in the case. As Gates left, she glared again at her partner, who was now laughing silently to himself. "Seriously, Castle? Just playing Flappy Bird?"

He laughed. "You should have seen your face!" He got high fives from the boys, who were now laughing openly, impervious to her deadly looks she shot in their direction.

"Don't you two have paperwork or something?" She asked, annoyed that they were egging him on.

"Oh, come on Beckett! It was funny!" Esposito pleaded, but one raise of her eyebrow told him she was not amused, and they dropped it, retreating to the break room together.

She sat at her desk, the new information in front of her, and looked again at Castle, who was watching her with mirth. "Well forget it. I'm definitely deleting Flappy Bird now."

His face fell. "No! Beckett, that's so not fair!"

She laughed at him. "You should have thought of that before you changed my ringtone." She opened her phone and fiddled with it, not really deleting the app because she knew he would want to play it eventually and she had a decent score, but looking up anyway, telling him, "It's gone." She then changed her ringtone back to the boring, work appropriate one it had been.

He shook his head at her. "You're no fun, detective."

She smirked at him and began poring through the financials, hoping to find a link anywhere that would give them a break. There was one thing her partner didn't count on though, and that was her need for revenge, because this was war. A few days later, she stifles her laughter in the crowded precinct as she calls him, and Barbie Girl starts blasting from his pocket.