Dean wiped the sandy dirt from his hands as he stood up. His body began a symphony of cracks and pops as his ankles, knees, vertebrae, and shoulders all complained to him about their age. It was a lie, of course, but one that always raised his hopes that maybe, just maybe, he'd actually hear them grow louder until his body reached its end.
Dead picked up the shovel and began to slowly fill the hole covering the curse box (actually it was more of a Russian nesting doll of curse boxes scrawled with danger symbols from every culture on Earth) containing the head of a Leviathan. The knowledge that it had taken Dean years to track this one down fed his hope that he was at the end of his task. It had taken so long to find the monster and he'd killed so many of them already. Soon he'd be done. Soon he could finally rest.
He'd finished filling in the hole, and had slung the wooden handle of the shovel over his shoulder when he heard the familiar sound that was like the sound of a flock of birds suddenly taking flight in panic.
“Hey, Cas,” Dean said, closing his eyes for a long moment, the hope that had been building within him became a source of pain, as if the edges had been sharpened with exposed razor blades. He opened his eyes and walked forward towards where he left the car. Castiel joined him, keeping pace to Dean's left without saying a word. Out of the corner of his eye, Dean could see Castie's dark hair shifting, and the flutter of the antique tan overcoat he still wore no matter how out of fashion it was. “Tell me that was the last Leviathan I had to kill.”
“Leviathan never die, Dean.”
“That's not what I meant and you know it,” Dean said, irritated. He reached the car, popped the trunk with the nifty app that came with his phone-watch and tucked away the shovel, slamming it closed. He paused for a moment to stare at himself, reflected in the clean plastic-glass blend thing they used now days. There were deep crows feet at the corners of his eyes. Around his mouth and crossing his forehead were deeply carved worry lines. His hair had turned mostly gray, although the few stubborn blond hairs lingered although they were barely distinguishable.
As always the sight of his own eyes made him look away from his reflection. He looked tired. Defeated. Dead.
He forced himself to look at Castiel, who still wore the body of Jimmy Novak. Who hadn't changed at all over the years. Who still looked back at Dean like he was the most amazing anything he'd ever seen. But also with a desperation and madness that made Dean sick.
Dean couldn't stand meeting his eyes either. He crossed his arms, and looked away from the deep well of Castiel's eyes, ignoring his own urge to beg to be let go. It wouldn't work. He'd tried it too often to think it would work today. Castiel never listened. “It took me six years to find that Leviathan, Cas. And it took nearly as much time for the one before. That was the last one walking free, wasn't it? They're all taking dirt naps now.”
Castiel didn't say anything for second. “Until they are returned to Purgatory, then they will always be a danger to this world.”
“Damn it, Cas!” Dean yelled, looking at the angel, his tempter getting the better of him. “It's been long enough. You promised. You said you'd let me go when I helped you clean up your mess.” Dean gestured angry at the buried curse box. “Well, it's done! I've killed every freaking Leviathan you let loose.”
Dean took a step closer to Castiel. Glaring down at the angel, wanting to hit him, slap him, and knowing it wouldn't make a difference other than him breaking his hand. “You promised,” Dean repeated in a softer voice, unable to keep from pleading. He forced himself to look into Castiel's eyes, desperately willing him to understand. Dean couldn't take much more. He lasted this long only by the skin of his teeth... any longer and he'd go mad. “You said you'd let me die. Cas. I'm nearly 500 years old. That's not normal. That's not human. I miss Sam. I miss Bobby, Ellen, Jo and everyone. You gotta let me go.”
For a second, Dean thought he'd finally, finally, gotten through to Castiel until the angel raised two fingers with all the ponderous weight of an executioner's ax and pressed them to Dean's forehead.
Instantly, the weariness of aged muscles and bones lifted off Dean like an unseen weight. The energy of youth flooded back into his body. Dean didn't have to look towards his reflection to know that he'd been returned to his prime. The wrinkles gone from his face, the gray vanished from his hair and all signs of aging gone along with the scars he'd picked up over the last few years.
The only thing which would remain the same would be his dead eyes. Castiel couldn't revive them with a touch. Dean closed his eyes. Despair choked his voice, strangling his denial into a pained gasp.
“I cannot follow you to Heaven,” Castiel said softly, as his fingertips brushed over Dean's eyebrows, drifting down to his nose and cheeks. He leaned close to press his mouth softly to Dean's lips.
As always, because Dean couldn't resist him. Because he was the only thing he had left in the world too. Dean kissed him back.
“I cannot let you die, Dean Winchester,” Castiel murmured when he finally pulled back. Then he was gone with the sound of a flock of panicked birds, fading in the distance.
Dean bowed his head, not praying, but trying desperately to hold on to the hope that was little more than ashes, losing heat like new corpse. Why bother? He'd been dreading the truth that Castiel never intended to let him die, however much he'd been telling himself otherwise. Now, he had the proof from the horse's mouth.
Castiel never intended to let Dean die. He never intended to keep his promise.
Dean swallowed, daring himself to consider the gun in his pocket and the swift end it would bring.
His fingers twitched and he was halfway in the middle of reaching for it when the spells marked into his skin and bones flared. Angel mojo stiffened all of Dean's muscles as he'd been hit with an electrical current. Pain burned along his nerve endings. He dropped to the desert ground. He couldn't even scream as his jaws locked in place. His spine arched, threatening to snap as it pushed to his body to the limit.
He shoved all thoughts of the easy way out from his mind.
“Okay, okay,” Dean gritted through clenched teeth. The pain faded away, slowly, as if to remind him it could be back at any moment and it wouldn't tolerate such thoughts.
Dean panted and stared up at the cloudless sky. The aching blue spread out before him, a vast land he would never touch as long as he remained an angel's obsession. Heaven was just a heartbeat out of his reach.
He stared upwards until he couldn't tolerate the longing anymore. Dean turned his face from the sky and slowly forced himself to his feet. He was wistful only for a second for the sounds of aging that he no longer heard his body produce, before he got into the car. The car hummed noiselessly and having been preset to take him home, he let it drive him back to his current cabin as he buried his young face in his callous-free hands as he wondered how old he'd manage to get before Castiel reset him again.
And how many times he would do it before Dean became as mad as Castiel.