They go out for ice-cream in the heat of the late afternoon; the weather feels more like July than May, too heavy, the warm air sticking to Kate's skin. Castle is looking for an ice-cream truck that is apparently heaven on earth - so many flavors, Kate, and most of them you never even thought could exist.

It doesn't exactly make her confident.

Their fingers are loosely intertwined, hands rocking between them as they walk; she cranes her neck to inspect the sky, the clouds that have started to flock together over their heads.

"Castle, I think it's going to rain."

He glances up, dismisses her words with a nonchalant smile. "Nah. The sky looked like that earlier. And the weather channel said the storm would only be tonight."

"If the weather channel said so," she mutters teasingly, rolling her eyes.

He tugs on her hand, eyes narrowed against her sarcasm. "Don't make fun of the weather channel, Kate Beckett."

"The weather channel gets it right about as often as Gates smiles," she points out, inwardly laughing at him and his antics.

"I don't think I've ever seen her smile," he observes thoughtfully.

Kate grins at him, arches an eloquent eyebrow. "Exactly."

He pouts at her, but just then music reaches them, a simple, repetitive tune that sounds like something from a children's cartoon. Castle's eyes light up as he turns towards the sound, leads them both around the corner.

"Ohhh, we found it, Kate!"

He sounds excited and happy, so very cute; she bites her lip to keep the smile in. Which becomes impossible once she sees the name of the truck. Big Gay Ice Cream. Really, Castle?

He looks back at her then, must catch the amusement on her face, because he lifts his eyebrows at her.

"Don't judge a book by its cover," he warns her, but he can't hold the scold - the bright joy is already piercing through.

She lifts up on tiptoe to land a kiss wherever she can - mm, she loves the corner of his mouth, the rough stubble that he hasn't bothered to shave - and murmurs in his ear, "Don't worry, Castle. I already knew you were metrosexual."

He goes for the Salty Pimp ice cream, just to see Kate's face - well, the combination of dulce de leche, sea salt and chocolate dip doesn't hurt either. He teases her for choosing the safest flavor - coffee - but then she adds cherry with a pointed look to him, mouth curving into a shadow of a smile.

He kisses her, feels her shiver from the cold ice-cream that lingers on his tongue.

When he backs away, Kate looks soft and tender, so beautiful he could weep just from looking at her. He's never been a huge fan of art - he likes going to museums, looking at the paintings, but he's never understood how people could just stand there and stare at a Botticelli for hours.

Until he met Kate.

"What're you thinking?" she asks when she's gotten her own ice-cream, and they're wandering aimlessly through the streets, shoulders brushing.

"How beautiful you are," he answers without thinking, captivated by the way her tongue swirls around the ice cream. She has a particular way of eating it; she first applies the flat of her tongue to it, takes one long lick, and then lets her lips finish the job, close over the ice cream in a sensual movement that is very much like a kiss.

She chuckles in surprise at his comment and turns her eyes to him; in the late afternoon light, they seem to have golden flecks in them. Her lips curl into a smile around the ice-cream.

"Sap," she says.

He shrugs, doesn't attempt to deny the obvious. "Doesn't make it any less true."

Kate keeps smiling at him but says nothing more, watching him with that wide-open love that is better than any words.

A drop of water crashes on her ice-cream. They're looking at each other, and the cone is between them; neither of them could miss it.

Kate's eyes widen and she looks up, just as the deep rumble of thunder resounds and the sky opens up above them. The rain is brutal, a curtain so thick that they can hardly see anything.

They're drenched in seconds.

"Castle," Kate gasps, and she grabs his hand, tugs him after her as she starts running.

Running to where?

Their ice-cream is ruined anyway; he was almost done with his, but he feels sorry for Kate (and even more sorry for himself, since it means he won't get to watch her eat it).

He ditches the rest of his cone in a bin, squeezes his fingers around Kate's to get her to stop, throw away her own cone. She gives it a mournful look, but there's nothing to be done: the ice-cream is already dripping all over her wrist.

He can't help himself; he takes her hand and licks it slowly, sucks all the ice-cream he can find, mixed with a healthy dose of rain. When he finishes Kate is on her toes against him; her eyes are dark under her lashes, her hair clinging to her neck.

He kisses her slowly, like it's the first time, their lips finding each other easily before he ventures his tongue out, relishes the way her mouth opens for him.

"Castle," she laughs into his neck, throaty and breathless, when they part. "We gotta find shelter somewhere."

"Why?" he asks. They probably can't get any wetter than this, and the sky is already clearing. He has a feeling that by the time they'd find a place with a roof, the rain would have stopped anyway.

So he just keeps kissing Kate Beckett in the rain; and although it feels a little like one of those cheap, romantic movies, the reality of her cold hands under his shirt and her teeth nipping at his lip is far better than any film he's ever seen.