A/N: By popular demand... don't try this at home. Or anywhere else for that matter. Because I have no idea if you'll be able to do it! Thanks to everyone who RT'd that tweet, and sorry it's not quite 2300 words or whatever you got it up to but hey at least I wrote something! Love you all, thanks for reading, enjoy, and please review.


FLEXIBLE

Castle leaned back against the soft white pillows, watching the bathroom door, waiting for Kate to come through it. They were in her apartment; Castle sometimes forgot how much he liked it. It was smaller than his and very different in most respects, but it was so Kate, so individual, neat but eclectic. The slightly shipwrecked feel it'd had when she first moved in had never quite disappeared.

"When are you going to move in with me?" he asked absent mindedly when she wandered out of the bathroom wearing nothing but a pair of his boxer shorts. She was slightly taken aback, but took it in her stride.

"I guess sometime after you ask me," she said, taking off the shorts. He looked up, grinning at her gorgeous body. She tossed her hair back and got into bed beside him, lying back stretching her arms out, running her toes along Castle's leg.

He moved, sitting up, nudging her legs apart and kneeling between them. He leaned down to kiss her; she arched her back, her mouth fitting to his in a way that never ceased to excite her. When they broke apart for air a little while later, she brushed her fingertips up his thigh. He reciprocated.

"I have so much respect for your legs," he mused. She chuckled.

"Come to my yoga class. You'll have even more respect then."

"No thanks. Anyway, you'd just get mad because you'd think I was looking at all the other women in lycra."

"Would you be looking at them?"

"Only incidentally. I mean it would be weird if I just sat there and stared at you."

Kate nodded. "Yeah. I suppose so."

She lifted one of her legs, swinging it up to gently rest her calf on his shoulder. He took hold of her foot, sliding his tongue across her instep. She pushed her other leg between his knees. He raised one eyebrow questioningly. She gave him a look as if to say, if you don't trust me by now you're a lost cause. He moved forward; she reached for him, rubbing her thumb over his tip, wrapping her fingers around him, moving gently until he was rock hard in her hand.

He took hold of her leg, gripping her thigh as he pushed inside her. She gasped, pointing the toes of her raised leg. He felt her muscles tense and flexed his hips, knowing he was brushing against her clit. This was affirmed by the moan that escaped her lips.

Kate kept her fingers near him, touching their connection, eyelids fluttering as he caressed her body with his free hand. She could feel him getting closer, enjoying the difference, the interesting new angle. She squeezed, and almost laughed as for some reason turkey basters popped into her head. They were only there for a second; the jerk of his body as he came was enough to send her shattering over the edge.

"Is that all you get from yoga?" he asked. Kate rolled her eyes. He kissed her, massaging her ass and the top of her thigh.

"I'm kidding," he teased her.

"You're right though," she said, teasing him. "That was only a taster."

"Pfft," he muttered, planting a soft kiss on her lips. He slowly moved his kisses lower, stopping at her neck to explore and suck the sensitive skin.

"You can't be..." she said, trailing off as his mouth found her breasts.

"Much as I wish you were wrong," he replied, kissing the join of her ribcage, "you're not."

Suddenly he shot backwards, tugging her by the legs until she was half off the bed. She giggled with surprise, a giggle that turned to a moan as his teeth gently nicked her inner thigh.

"Will you really move in with me if I ask you?" Castle asked. They were both sitting on the floor at the foot of the bed. Kate chuckled.

"You can't ask what'll happen if you ask. You just have to ask."

"Mm..." He stood up, holding out his hand to her.

"Did you wash your hair before?" he asked.

Kate smiled. "No."

"Dirty girl."

She laughed, letting him tug her to the bathroom. She could tell he was ready again; she put her arms around him as he turned on the shower above the tub, holding him from behind, kissing his back, teasing his chest with her fingernails. He stepped under the flow of water, she stepped with him, her hands getting lower and lower. He turned around when they reached his abdomen and put his hands on her hips, positioning her against the wall. He was fully under the stream of water now; it ran in attractive rivulets over his hair and face and down his body. Kate put one foot up on the side of the tub, by way of invitation. Castle was more than ready...

It was a while before her hair was clean. When they finally left the bathroom Kate threw a towel across the bed and lay on it so she could be comfy without getting the sheets wet. Castle lay down beside her, very close, so as to stay on the towel.

"Will you move in with me?"

"I'll think about it," she replied, not looking at him. He was about to make a very injured sounding remark when she took his hand.

"Of course I will, dumbass," she said fondly.

He held her hand tightly. "I love you."

"I'm marrying you, I wasn't exactly going to say no. For a smart man you can be really-"

He cut her off with a kiss. When they were lying still again Kate had a thought.

"Would you dry my hair for me?"

"Sure," Castle said, wondering what else she was thinking. Kate got up to get her hairdryer, plugging it in and handing it to him. He waited for her to sit back down in front of him but instead she beckoned him to the edge of the bed, kneeling down, kissing his thigh.

"Wait, you want to-"

The question became unnecessary. Kate reached up to turn the dryer on – Castle seemed a little distracted, but after he'd properly caught on he started working on her hair, running his fingers through it in place of a brush, only jolting occasionally, while she worked on him.

He sensibly put the dryer down in time; Kate swallowed down everything he gave her, enjoying the feel of him filling her mouth. She slid off him with a pop, kissing him one last time before standing up and examining her hair in the mirror.

"You're so well trained," she said admiringly. He pulled her back onto the bed beside him.

"You're so..." but he didn't finish the sentence. She laughed.

"What? Weird? I don't mind if you think so. I've just always wanted to do that."

He smiled, stroking her hair again. "No, not weird. I liked it. You're just... You're different than any person I ever met, Kate. So different. So powerful, so strong, so brave, yet also so considerate, so thoughtful, so..."

"Are you sure this isn't the blow job I just gave you talking?"

"Way to ruin the moment, Beckett!"

Kate lay back on the bed.

"Sorry. Well, thanks. You're different, too. When I first met you I thought you were so wrong for me, I thought we'd clash constantly, I thought... But I've never met anyone so right for me, anyone who fits so well with me."

He looked down at her, raising one eyebrow.

"I meant personality wise," she said, laughing. He leaned down and kissed her, tasting himself, tasting sex, tasting the mingled, subtle flavour that was them, private and dark but also light, free...

He fetched her a glass of water from the kitchen, looking around at the apartment again as he went.

"I'll miss it here," he said to himself, filling the glasses that didn't match, tapping his fingers on the wooden counter.

"Beckett?" he said as he came back into the bedroom.

"Yes, darling?" she said in a mildly mocking tone.

He handed her the water.

"Can... Can I move in with you instead?"

She smiled. "That's sweet, Cas, but I know you haven't thought it through. Where would you write? Where would you put all your stuff?"

Castle sighed. "Okay, so... Well can we at least keep this place?"

Kate bit her lip in the way she knew he loved.

"I... Honestly, Castle, I feel far more at home with you than I've ever done in a place. I like this apartment, but we don't need two. How about, instead, you just let me do some redecorating, bring some of my stuff to your place? We can make it ours, put them together, like the shell thing in your room."

Castle sat down on the bed. "Yeah, I guess... I just... I like that this place is so you."

Kate smiled. "I'll bring me wherever I go."

Castle wove his fingers in between hers, smiling as he touched the ring on one of them. Kate put down her glass and scooted down the bed, resting her head on his chest.

"Know what?" he said, putting down his glass too and kissing the top of her head.

"What?" she asked sleepily.

"September," he murmured.

"September," she echoed softly.