Dean hears the tell-tale swish of a trenchcoat approaching and looks up from the book he had been flipping through. It had been a shock to Sam the first time the younger Winchester walked into the room and saw his brother reading – actually reading – but it was the first time in a long time that Dean actually had the time to relax and enjoy a good book. Living in the Batcave had all kinds of perks that he was really enjoying – plenty of hot water for showers, plenty of space to avoid his brother, no more being crowded together in dingy, dirty motel rooms. He had his own bedroom, for Christs sake! It was awesome. And the silence. Ah, the quiet... it was so nice. So peaceful that he could actually hear the swish of a trenchcoat from the next room. Which reminds him – Cas.

He kicks his feet off of the couch and sits up straight, turning around to face the blue-eyed man with the sleep-mussed hair that seems much too small for that coat ever since he lost his grace. And it's not that Castiel is different at all physically – he's the exact same size, it's just that he seems so lost, so empty, so scared and curled in on himself. His shoulders slump, his head droops, and his eyes are... well, they're still that piercing, electric blue, they're just a little bit dimmer than before. Like he lost a bright sparkle of hope along with his angelic status.

He's gotten used to being a human well enough. He sleeps a lot and tends to wake up in a state of panic, not used to being unconscious for so long, but the bouts of fear have gotten less intense and less frequent throughout the past month. He still likes to wear his trench coat all the time even though he now has his own set of clothes, since he tried wearing Dean's and they swallowed him whole (Dean will not admit his disappointment at that fact, because he is not disappointed that Cas stopped wearing his clothes – nope, not one bit, he doesn't care). He's eating like a champion; Dean has been feeding him probably more than necessary to ensure that he doesn't lose any weight, despite the fact that Castiel insists that he's not hungry, because they've started doing a little training. That seems to be unnecessary too, because although the guy lost his grace, he sure hasn't lost any of his fighting skills. In fact, he's given the hunter a pretty decent ass-whooping more than a few times. So overall he's doing well, but he still seems... sad. Very, very sad.

"Hey, Cas," Dean greets him softly, noting the even-more-scared-and-upset-than-usual expression that the ex-angel is sporting. "How you doin', man?"

"Fine," Castiel sighs. He makes his way over to the couch and shifts on the balls of his bare feet, as if he wants to sit down, but doesn't think he should. He's huddled inside his trenchcoat but the collar of a navy blue t-shirt and a pair of jeans are visible from underneath it.

Dean clears his throat and puts his book off to the side. "You, uh... you wanna sit?"

The dark-haired man perches hesitantly on the edge of the cushion next to the hunter and rests his hands on his knees, fingers flexing and relaxing in an erratic rhythm.

"Are you okay, Cas?"

"No, Dean, I am not okay," Castiel snaps. His eyes widen and then he composes himself. "I apologize. I..." He takes a deep breath. "I am having a... problem."

Dean turns to face his friend, concern settling over his entire body like a blanket. "Yeah, okay. I'll help you out. What is it?"

Castiel shakes his head and his voice rises shakily. "No, you cannot help me, Dean, that is the problem. You are the problem. It is... every time I am around you, I have this... this feeling that I do not understand, and I tried to talk to Sam but he said I needed to talk to you, and I am worried that you..."

"That I what?" Dean's shoulders have tensed up defensively, but mostly he's just concerned, and hurt that Castiel feels like he can't talk to him. What did he do wrong? He couldn't possibly... Castiel couldn't possibly know that he...

"That you will be angry," the ex-angel interrupts his thoughts quietly. He looks down at his hands as though he's ashamed, and Dean's shoulders relax as his heart breaks for his friend.

"Cas, I won't be mad at you," he reassures him. "I promise. You can talk to me."

Castiel looks back up at him with those eyes, those beautiful blue eyes that have lost their extra sparkle, and suddenly Dean feels afraid, like Castiel is looking straight through him. He's always had that sort of effect whenever he stares at the hunter, but this time it's even more intense and even more terrifying, because Dean can't help but think that Castiel knows. Knows about the decidedly more-than-friendly feelings he's been having as of late, knows about the X-rated dreams that make him moan in his sleep, knows that he's been thinking more and more about what it would be like to wake up to a pair of familiar blue eyes and a head of dark, bed-mussed hair. But Castiel can't know. He can't.

"Dean..." The gravelly voice sucks him out of his own mind, drowns him in the warm feeling that bubbles up in his chest at the sound of his own name falling out of those chapped lips. "You are... you are..." He closes his eyes and makes a throaty, frustrated sound. "You make me very uncomfortable."

Dean feels nauseous. This is it, he's scared Castiel off because he can't control his own goddamn emotions and now they can't even be friends, now they can't ever be anything more. Why does he always have to go and fuck everything up? And those three words keep repeating like a broken record in his mind: This is it.

"Every time I see you, I feel..." Castiel searches for the words in his eyes, gazing deep, so deep that he could probably see the very soul he pulled out of Hell, the soul he probably regrets ever even touching. And here Dean was thinking that he meant something special to the ex-angel, that he was important. That he was hand-picked because of something a little deeper than simple orders.

"I feel warm," the dark-haired man continues, and Dean blinks in surprise. "I become light-headed and my chest is... full. It feels as if I am going to explode. And I get very..." Castiel averts his gaze now, instead opting to look down at his hands, still nervously clenching and unclenching the material of his coat. His voice is barely more than a whisper when he finishes, "I get very hard."

Dean sits in silence for a moment, trying to comprehend what he's hearing, because he can't make heads or tails of it. It doesn't make any sense. "Hard?"

With an exasperated huff, Castiel explains embarrassedly, "My penis... becomes hard. I believe it's called an erection."

The hunter's spring green eyes get as wide as dinner plates and his jaw drops. He sure doesn't feel sick anymore; the nauseous feeling has been replaced by... butterflies? Oh god, no. Too girly. Besides, they feel a hell of a lot bigger than butterflies – fucking pterodactyls, maybe. Yeah. Christ.

"I make you hard?" he repeats, still unable to process the information.

"Yes, Dean, you arouse me," Castiel clarifies. His cheeks are bright red and he looks so nervous and it might actually be one of the most adorable things Dean has ever seen in his life but maybe he's just thinking that because he's so happy. "I apologize if you... if you are uncomfortable, but I just do not understand... I tried to talk to Sam, but he just told me to –"

"You asked Sam?" Dean interrupts bluntly. "Seriously? You told Sam I turn you on?"

"I did not know what else to do," Castiel snaps in defense, finally bringing his gaze back up to match the hunter's.

Dean's expression softens almost immediately, and the corners of his lips turn up in a genuine smile – not a smirk, but an actual, warmhearted smile. "You could've just told me, you know," he murmurs.

"You are not angry?" Castiel blinks innocently, relief relaxing his entire body.

"Of course not!" Dean reaches a calloused hand up to cup the ex-angel's cheek. He strokes Castiel's cheekbone with his thumb. "Guess what?" he whispers, leaning in closer.

Castiel's breath hitches at the hunter's movement and chokes out, "W-what?"

"You make me hard too," Dean breathes, and he would be grinning at the stupidity of his declaration of affection, except that there's just a sliver of space between their lips and he could close it if he moved forward the tiniest bit and it overwhelms him so much that he freezes for a second, heart hammering away in his chest, just sharing air with Castiel –

– until suddenly they're touching, Castiel has closed the last of the distance and they're kissing now, light-stubble brushing against freshly-shaven skin, Dean's hand moving back to Castiel's neck and tightening its grip, both of them letting out a heavy breath that neither had been aware of holding in.

And then Castiel is clambering onto his lap, swinging a leg around to straddle his thighs, and Dean's hands are on his back, on his ass, pulling him closer, running his tongue along Castiel's lower lip and then sweet merciful heavens he's inside Castiel's mouth, tasting, sucking, nipping, and Castiel is clawing at his shirt, and he decides that enough is enough and if that's where this is headed, damn it all if he isn't going to do this right.

He wraps a strong arm around Castiel's lower back, keeping the other hand planted firmly on the ex-angel's ass, and pushes himself off the couch with his legs (and he's never been so thankful for his muscular thighs as he is now). And Castiel wraps his lithe legs around his waist, holds onto his broad shoulders with all the strength he can muster as Dean walks them out of the living room, down the hall, fumbles for the door handle and stumbles into his bedroom, barely managing to kick the door shut behind them before they're falling onto the bed, legs and arms and tongues tangled in a sensuous dance.

And somewhere between the articles of clothing, somewhere between the shirts and pants and boxer briefs, Dean throws the safeguard around his heart across the room too, and realizes that this is what he should have been doing the whole time, this is where he belongs, this is the reason he matters. The reason is kissing him as though his life depends on it, worshiping his body, making such sweet love to him that overwhelmed tears gather in the corners of his eyes. The reason gave everything for him; his life, his family, his power, and would do it again in a heartbeat, simply because he wants to. The reason has dark, perpetually messy hair and blue, blue, blue eyes that seem to have suddenly gotten their sparkle back. And the reason's name is Castiel.