The first time he kisses her in the precinct it's innocent, sweet, not even on the lips. They're both tired, a little out of it, and he doesn't even think about it. He helps her into her coat. She pulls her hair out of the collar, turns to face him, and he leans in, presses a soft kiss to her forehead.

She sighs a little, places a hand on his chest, lets her eyes slip shut for a moment. It's so natural, so easy, that it doesn't register until she turns to get on the elevator and sees Ryan staring at them a little wide-eyed, blushing furiously.

Kate freezes, causing Castle to bump into her back. He grunts a little, still not catching on. "Shit," she breathes.

Ryan drops his eyes to the floor, looking like he wants to disappear into the floorboards.

"Castle," she groans, pressing a hand over her eyes.

"What?" he asks. "What is it?"

She turns to face him. "You kissed me," she hisses.

"What?" he squeaks. "No, I…no I didn't." She gives him a look, taps her forehead, and his face falls. "Crap. I did."

They both turn back to Ryan simultaneously, who is studiously not looking at them. He looks embarrassed, but the way his eyes shift, the pinched line of his mouth, makes him look almost…guilty.

Castle's brow furrows in confusion. Huh. Strange.

Kate steps towards the other detective. "Look, Kevin…"

"I already knew," he blurts out before she can finish her sentence.

Castle smirks. Well, that explains the guilt, then.

Kate is not amused. "Ryan, what the hell? You knew? For how long?"

Ryan opens his mouth, then closes it. He shoots a desperate look to Castle for help, but Kate catches it and gives his arm a sound smack. "No, your buddy isn't going to get you out of this one. How long have you known?"

Ryan sighs and Castle almost feels sorry for him. Mean Beckett is scary. "A couple weeks," he murmurs.

Kate smacks his arm again and Ryan lets out a little huff, rubbing his shoulder. "Why didn't you say anything?" she demands.

"Because I…I didn't want to mess it up for you guys, okay?"

Kate pauses, considering that. "So you…didn't tell anyone else?"

"What? No! Of course not. I knew if Gates found out she'd make Castle leave and I…I didn't want to do that to you."

Castle watches as the information settles on Kate's face. Her lips twitch slightly, then part into one of those bright, dazzling Beckett smiles and then she's launching herself at Ryan, wrapping her arms around his shoulders in a fierce hug.

"Thanks, Kevin," she murmurs.

Ryan grins, looking pleased and a little sheepish at the sudden display of affection.

"You two need to be more discrete," he announces when she pulls away, straightening his coat and giving them both a look.

"We will be," Castle promises, walking over to stand beside Kate.

Ryan looks at them and rolls his eyes like they're hopeless. Castle glances down and realizes he's holding Kate's hand. He pulls it back quickly, shoving it in his coat pocket. "We'll be better," he says again.

Ryan just smiles and shakes his head, moving off in the direction of the elevator.

"We definitely need to be more careful," Castle says once he's gone.

Kate turns to him, eyebrow arched in amusement. "We? Clearly, you're the one with zero control in this relationship."

"Hey, I think I recall someone ripping some buttons last night. That was my favorite shirt by the way."

"Again, your fault," she says.

"How is that my fault?"

"That phone call?"

Castle grins. "Oh yeah. That was good, right?"

She groans at him. "I was on the subway, Castle."

"Who knew Kate Beckett liked phone sex?"

She just rolls her eyes and spins on her heel, heading towards the elevator.

"Any other kinky things you want to try out? Bondage? Whips? Roll playing?"

"Shut up, Castle."

"Fine. But seriously, when are you going to show me that thing you do with ice cubes?"

—

Short and sweet. Sorry I haven't updated this in a while. I haven't had much time to write lately, but I'm hoping to get back in the swing of things. As always, reviews are almost as wonderful as chocolate when you're PMSing so drop some knowledge in that little box if you have a sec. Suggestions for more firsts would be greatly appreciated!