The first time they kiss, they're on a playground. Jimmy is being a brat, teasing him about his best friend and Castiel hides in the top of the slide, hunched over his feet and blue eyes furious.
Dean finds him there. "Jimmy's a jerk," He says succinctly. Leans over and kisses Cas's cheek, same as he'd do his new baby brother, Sammy.
And it gets the same reaction. A shy smile blossoms and Dean grins at his friend. "Race you to the swings."
The second first kiss is also because of Jimmy. He's dating that girl, Amelia, and Cas is already a little odd. A little different.
He doesn't understand why his brother has forgotten him so easily.
That and Jimmy's comment has him sprawled across Dean's bed, glassy eyed with anger, his hands clenched into fists.
"More than anything, I hate that he's right," Cas admits, and Dean huffs.
"Jimmy is an ass," Dean snaps, and leans over, jostling Cas and invading his space and pushing plush red lips to chapped pink ones. Cas goes startled next to him and kinda opens his mouth and Dean touches the tip of his tongue to Cas's.
He jerks away, eyes huge and lips shiny as Dean grins at him. "And now he's not right. You've has your first kiss." Dean slaps his shoulder and sits up. "You staying for dinner?"
Their third first kiss is on prom night. Senior year. They go with their dates, together, and it should be great.
It's not. It goes wrong, spectacularly wrong almost before they get there. Meg is buzzed and hanging al over Cas and Dean is stiff and angry, almost ignoring his date, which causes a fight in the Impala while Meg adds sly commentary and Cas does his best to shut her up. As soon as they arrive, Cassie abandons Dean in favor of her best friend, a dark skinned boy who dances with her and glares at Dean. Meg smirks and dances with Cas until she gets a better offer and leaves with the promise to be back in five minutes.
Two hours later, they're both bored and Dean can't handle Cassie's behavior any longer. Castiel drags him out of the venue and onto the lit up sidewalk and Dean huffs a sigh.
"Cassie is a bitch," Cas says softly and Dean nods. They walk, kinda aimless, for a while until his phone goes off and he gives Dean an awkward smile. "Meg is looking for me."
Dean nods and waves him away, and when he hesitates, Dean leans over and brushes a kiss across his lips, a silent thank you and breathes, "Go on, Cas."
And with a worried smile, he does.
The fourth time, Cas is hunched in shock. It's been years since prom and so much has changed but two things haven’t: He still is different and Dean is still his best friend. College, girlfriends, and burgeoning careers hasn’t changed that at all.
He's sitting on a couch in a dark suit and a rain splattered tan coat, looking like his world just ended.
He isn't completely wrong.
A few feet away, the baby whimpers in her car seat.
"Cas," Dean says, sitting next to him. "Cas, I am so sorry. Jimmy was a good man."
Cas snorts and wipes his eyes. "He was an ass. But he was my brother."
Dean nods and the baby shifts at their voices and starts to cry.
Castiel stares, blank faced and panicked.
Dean, however, has two nieces now and a brother he raised. He scoops up the whimpering little girl and rocks her against his shoulder while he makes a bottle with one hand, crooning a Kansas song to her as he waits for it to heat.
When he turns around, the baby quiet and happy with her bottle, he's startled to see Cas in the doorway, watching him.
"What am I gonna do?" Cas whispers. "I don't know how to take care of a baby."
Dean leans over and kisses him, a quick brush across his forehead and Cas looks up at him, startled.
"I do, buddy. We can do this."
The fifth time is less than a year later. A hard year. Claire is not an easy baby and Castiel is still reeling from the sudden death of his brother and Amelia. Even having Dean down the hall and helping, he feels like he's drowning.
But it's not always a bad kind of drowning. When he wakes up in the middle of the night to the sound of music and finds Dean rocking Claire back to sleep. When he works from home while Claire naps and looks at the clock to realize that Dean will be home soon and he should start dinner.
And now. When he looks across the couch and Dean is warm and sleepy next to him, watching the New Years Eve festivities on TV, Claire asleep between them on the couch.
This feels right. It feels good.
And it scares Cas.
"You didn't have stay. With me. Us."
Dean glances at him, amused. "I know, Cas."
"Why did you?" Cas asks. Dean shrugs.
Leans over the sleeping baby and kisses him. Soft and chaste and sweet.
And confusing the hell outta Cas.
"I wanted to."
The last first kiss came with another auspicious first.
Claire's first day of preschool.
They've been raising her together now for two years, and if it's strange, it works for them. Every once in a while Castiel suggests he could be happier somewhere else. With a girl and a family of his own and Dean always ignores him.
A few days later, he would get blind drunk and angry, though, and Cas stopped suggesting it because he hated seeing Dean self-destructive.
And because Claire adored her Dee.
Sometimes, John would make noise about the whole thing. Sam shut that down as often as he could.
So they were happy, if odd.
But that day.
Dean took the morning off work, and Cas hid his smile as his big manly best friend completely lost his shit over sending their girl to school.
Claire, naturally, was calm and collected the whole time and skipped into her class without a care in the world, shouting, "Bye, Daddies!" Over her shoulder.
Dean went stiff and startled next to Cas as Cas sorted through that.
She called him Daddy.
She called them both Daddy.
"Dean we have to go now," Cas said, when Dean wouldn't budge from the doorway, watching the little blonde girl with a kind of desperation that hit Cas hard. A mom with a dark haired boy squeezed past Dean and sent him an appreciative look that annoyed Cas.
"Is she ok?" Dean asks, his voice shaky and vulnerable.
Cas squeezes his hand, and Dean startles, looking at him.
Something terrifying and hopeful shinning in his tear filled eyes.
Cas smiles, and everything makes sense. All of it. All of the years and Dean makes sense. He smiles. "Yeah, babe. We're all gonna be ok."
Dean whimpers, honest to fuck whimpers when Cas leans over and kisses him in the doorway of their daughter's preschool class.
He's smiling, eyes shiny and so damn happy, when he presses his forehead into Cas's and mutters. "You ass, you picked here?” The words brush against Cas’s lip, and the tip of Dean’s tongue flicks against Castiel’s lips. He sighs, a happy noise Cas is sure he’ll remember until the day he dies. Whispers, “Fucking finally."
Cas laughs into his mouth, and kisses him again.