Summary: Cas never thought he'd see Dean again after he left the Men of Letters bunker, but when disturbing occurrences elicit a call to the hunter, Cas will discover that there are some things you can't just walk away from. Takes place in Season 9 episode 6 "Heaven Can't Wait"

"Where to, Cas?"

Cas glanced up at Dean over the roof of the Impala, centering his gaze on the shadowed green of Dean's eyes, and felt that familiar warmth settle low in his belly. He had certainly been surprised when Dean had shown up at the Gas-n-Sip yesterday, had actually been completely caught off guard, and in that moment had only been able to feel an unsolicited anger well up inside of him. It had been hard enough for him to walk away from Dean in those early, pre-dawn hours, to leave the bed they had shared such a short time ago - a few short weeks that had seemed like an unbearable eternity- but to see him standing before him had broken that carefully constructed wall he had fought so hard to put up around his heart.

Just hearing his voice over the phone when he had called Dean to inform him of the disturbing situation in the town he had settled in had sent a shearing bolt of pain straight to his heart. Seeing him standing before him yesterday morning had damn near killed him. And it had been all he could do to push down all that hurt and anger and longing that had suddenly scorched through him and threatened to overwhelm him.

He had walked away from the Men of Letters bunker on his own accord, had made that decision for Dean because he had seen that pained confliction on his face and had only wanted to shoulder that burden away from him. But it had not been easy to slip away from Dean as he slept, and he was still hurt and confused as to why Dean had pushed him away in the first place, still uncertain if it was because Dean really did see him as a threat to Sam's safety, or because without his grace, he was essentially useless.

But he had to admit to himself that he was glad he had called Dean; he owed him his life once again, and knew that without Dean there, Cas would only be so much of a fine pink spray across the walls of Nora's living room.

Cas' stomach churned uneasily and he pulled his gaze from Dean, glancing down to his hand on the Impala's door handle. Vulnerable, Weak, Helpless. He let himself into the car without another word, but not before catching a perplexing glint of eagerness in Dean's eyes.

Cas slumped down on the supple leather of the car seat, letting out a heavy sigh. Dean only continued to confound him. The whole time Dean had been here, he had been nothing but smiles and encouragements and dating tips, like it didn't matter how much Cas was hurting inside, how much his heart had ached nearly every single day since he left.

Cas looked down at his hands, at his bandaged wrist, as Dean slipped into the driver's seat beside him. Cas knew he'd be lying if he said that the firm, warm feel of Dean's hands on the delicate skin of his wrist's pulse point when he had expertly splinted his injury didn't send a jolt of desire coursing through him. And he knew he'd definitely be lying if he said he didn't think about the brief moment they'd shared in that small bunker room every single night before he'd gone to sleep in the supply closet in the back of the Gas-n-Sip, stroking and pulling at his cock in a poor attempt to replicate the feelings he'd experienced that night.

But things had changed in so many ways since then, and while the pain in his chest had lessened somewhat since he had been apart from Dean, having him beside him for what he knew would be a short time sparked that hurt back into a scalding hot flame because he knew that, this time, their separation might break him in a way that he'd never be able to recover from. The only way Cas knew to protect himself was to throw up those barriers again, to try and walk away from this with as much of his heart intact as possible.

He felt Dean's eyes on him and he turned slightly in his seat to look over at him. The glow from the Impala's instrument panel reflected in his eyes, lending to them a hungry green glimmer as he looked at Cas expectantly.

"So? Where to?"

"Just drop me off back at the gas station," Cas replied, careful to keep his voice even.

The crooked smile on Dean's face faltered for a moment. "What, really?" he asked, incredulous, the smirk reappearing back at his mouth.

Cas straightened in his seat and he centered his gaze out the windshield. "Yes." He reached for his seat belt, wincing when he inadvertently jostled his wrist.

Dean chuckled softly and leaned over to reach across Cas, brushing his arm against Cas' chest, sending desire arrowing straight to his groin at the fleeting touch. "Here, let me help with that," Dean said, grasping for the seat belt.

"No. It's fine. I may be useless, but I can do that much myself," Cas said sharply, fumbling for the belt, feeling pain shoot through his arm at the movement, but centering his focus on that ache rather than the arousal that tried to cloud his mind.

Dean sat back abruptly, his hands held up, a scowl darkening his features. "You arenot useless, Cas. I was just tryin' to help you out."

"You've done enough Dean, really," Cas said as he secured the belt. He regretted the biting remark almost as soon as it left his mouth, but did not apologize for it; they were just more bricks he could use to wall up around his wounded heart.

Dean only stared at him for a moment, and when Cas did not turn to meet his gaze, huffed out a darkly bemused grunt before throwing the Impala into first and tearing away from the curbside.

The drive to the Gas-n-Sip was short and filled with a tense silence, and by the time they pulled to a stop in the darkened parking lot, Cas was more than ready to get out of the car before he said words he'd regret, before he did things that would only end up hurting him.

Dean slammed the Impala into park and drummed his fingers on the steering wheel. "Grab your stuff and I'll drive you to your house," he said tersely, not even bothering to glance in Cas' direction.

Cas fidgeted in his seat for a moment before speaking in a quiet voice. "This is it, Dean. This is where I'm staying."

Dean barked out a harsh, humorless laugh. "You gotta be fucking kidding me, Cas."

Cas unbuckled his seat belt and turned to look at Dean for the first time the whole car ride, that unwanted anger bubbling sourly in his stomach again. "I told you already, Dean. When I lost my grace, I lost everything. It might not be much, but it is an honest living and It. Is. All. I. Have." He stabbed his finger at the gas station and enunciated each word carefully, his voice bordering on a shout.

Dean seemed taken aback before his features softened and became sullen. He looked away from Cas, staring out the windshield, his fingers clenching and unclenching over the steering wheel - fingers that had gripped Cas' hips so tightly, the fading bruises still marked his skin. Cas blinked away the memory and saw Dean's adam's apple bobbing visibly as he swallowed.

"You didn't lose everything, Cas," he said thickly. "I'm still here."

Cas kept his eyes locked on Dean's profile. "I have lost that as well. I lost that the day I chose to leave the bunker and step out into this world alone, for Sam's well-being, to unburden you from my own uselessness."

"Goddammit, Cas! How many times do I have to fucking tell you? You are not useless!" He turned to face him, his grip tightening over the steering wheel. "You think I liked seeing you go on a date with someone else? You think I like watching you livin' this happy, normal life without me in it?!" He shouted the words at him. "Findin' that bed empty that morning you left, Cas, it tore me up inside. Not being able to see you or hear your voice every day is fuckin' killing me. And if there's anyone that ain't got nothing here, it's me!" he roared. His bottom lip trembled and he quickly pressed his mouth into a thin line. Angry tears glittered harshly at the corners of his eyes. "You could have at least said goodbye, for fuck's sake Cas!" He looked forward again, his chest heaving, as a single tear tracked down his cheek. He scrubbed it away harshly and let his hands fall to his sides.

And all the reservations Cas had been holding onto, all the bricks he had tried laying down, fell away in a great rush. He crawled across the wide expanse of the bench seat and swung his leg over Dean's, straddling to face him, feeling the angles of the steering wheel bite into his back as he settled over his lap. Dean's eyes, pained and angry and wounded, the first sincere expressions Cas had seen him show since yesterday morning, searched Cas' face desperately.

Cas brought his hands up to frame Dean's face, feeling the slight rasp of his stubble scrape his palms. "It was never my intention to hurt you Dean. I was only attempting to spare you from the pain of having to make the choice between me and your brother. Please forgive me," he spoke the words with an earnestness that welled up from somewhere inside of him and spilled out into the kiss he slowly pressed to Dean's mouth.

Dean was still for a moment, until Cas parted his lips with the gentle insistence of his tongue, and then his hands came up, settling firmly against Cas' hips, pulling him closer, moaning into his mouth.

Cas' hands slipped up into Dean's hair, tangling in the strands, holding his head still so that he could pull in a long, slow taste of Dean's mouth. The hard press of Dean's cock suddenly dug into Cas' thigh as he continued to straddle him and he rocked forward, the movement and resultant friction eliciting a groan from both men.

Cas' own erection strained almost painfully against his jeans and he suddenly had a very intense desire to be free of the confining clothing. He glanced up to Dean's eyes, darkened almost to black by desire, and he nodded.

Cas moved off of Dean only long enough to tug his jeans off just as Dean unzipped his own fly and shimmied his pants down just enough for his hardened cock to spring free. Cas scrambled back across the seat, throbs of arousal thumping to his groin with each beat of his heart, and watched as Dean brought a hand up to his mouth and spit into it. He quickly slicked his cock with it, his head falling back, his eyes closing as he stroked himself. Cas felt like he could watch Dean pleasure himself for time without end, but Dean quickly opened his eyes and looked over at him, his eyebrow raised.

Cas wasted no time in swinging his leg up over Dean's lap again, moving his hips forward so that Dean's cock was centered right at his entrance. His own cock stood rigidly, curving up toward his belly, aching for touch.

Dean settled his hands on Cas' hips again as Cas slowly lowered himself onto Dean's cock. Cas brought his hands up to Dean's shoulders to leverage himself, and felt Dean breach his entrance. He let out a long shuddering moan as Dean slipped inside of him with a slow, gentle push and watched as Dean's eyes fluttered closed.

His eyes flew open when Cas pushed down all the way in one quick motion, settling himself flush against Dean's thighs, his mouth formed into a soundless O of pleasure.

Dean let Cas set the pace at first, shallow, quick thrusts, to give him time to adjust. Cas fisted his hands into the fabric of Dean's shirt at his shoulders when Dean suddenly gripped his hips tightly, shoving Cas down on his cock roughly. Twin moans echoed in the heated confines of the Impala.

"Oh God, Cas. This is just…" His words faltered and he gritted his teeth, his eyes squeezing shut. And then Dean's hand, still slicked with his own saliva, was wrapped around his cock, twisting up over and over. Cas gasped, his head falling back, letting Dean's name fall from his mouth in a whispered rush of Enochian.

"I need you Cas. I'll always need you," Dean groaned coarsely, the cords of muscle standing out at his neck, pulling Cas down roughly, holding him still against him as he came forcefully.

And with a final twisting pull of Dean's hand, Cas was lost too, spilling over Dean's fist with a strained cry.

He leaned forward, resting his head on Dean's chest, hearing the rapid pounding of his heart under his ear, as they both fought to catch their breath.

"We'll figure this out together, Cas," Dean said huskily against Cas' hair. "We'll figure out a way to make this work, cause I'll be damned if I ever lose you again."

Cas nodded against the sweat soaked material of Dean's shirt under his cheek, feeling more contented and sated in that moment, huddled in Dean's arms, surrounded by their intermingling scents, than he had for weeks. And he knew that this life he had tried constructing, this neat, organized, normal life, could never come close to fulfilling that longing he had felt for millennia, not when that emptiness could only ever be filled by Dean's presence, even if he was not right at his side.

"Will you come to my hotel with me?" Dean's voice drifted down to him, and he could only nod, knowing that even if he didn't have a choice, if he was never even given one, Castiel would always choose Dean Winchester.