A/N: Recently I have read a fic by Revhead called Let Go. I don't want to spoil anything in this AN, so I recommend you check it out, you won't be disappointed! Anyway, after reading, I thought that I would write a tag to this story (which Revhead was gracious enough to allow, thanks!). I would definitely suggest reading the fic before this one, but mine can be taken as a stand alone as well. I hope you enjoy!

At first, they were the best years of his life.

Sure, the Mark of Cain had stolen his mortality.Nothing but the First Blade itself could end his life. But he was still Dean Winchester. At first, it had horrified him that he had essentially become one of the very creatures he and Sam had hunted; every now and then, his eyes would flick to that inky blackness that would never fail to remind him that he was no longer human. But being a demon had its perks too. Already an excellent hunter, Dean was now unstoppable. Cas had buried the First Blade in the depths of the North Atlantic, where no man nor creature would ever retrieve it. The enemies who once ridiculed him feared the Winchesters; and those who were already leery of the brothers fled in terror. And Castiel would always be there, to keep his humanity. Dean's greatest fear upon learning his fate was that he would one day become more than just demonic in name. The angel would always be there to keep him sane.

And there was Sam. With his new found status as Knight of Hell, Dean had even more power to protect his younger brother with everything he had. Carrying him, both literally and metaphorically, was simple; and Sam, having finally understood his brothers intentions the night the angels fell, was grateful for his brother's efforts. It still frustrated the kid at times. He still had to remind Dean that sometimes, he needed to do things for himself. And the eldest respected that. But Sam, having believed his brother dead at the hands of Gadreel, having heard that his pain in the ass older brother had tried to kill himself, was reminded that, as selfish as his brother's actions that night may have been, the intentions had been pure. Best of all, Sam had referred to him as his brother. Not partners, but once again the brothers Winchester. The relief Dean had felt in those moments as his brother embraced him had left him overwhelmed. He had his brother back. The one Dean had been so afraid would be terrified of him, would want to kill him. The one who was now struggling to regain his composure after days of fearing he would never see his brother again.

The brothers continued to hunt, eventually defeating Abaddon, Metatron, opening the Gates of Heaven and slamming those of Hell shut for all eternity. The brothers retired from hunting, Sam finally finishing his law degree and Dean working full time in a garage. At first, no one questioned how a man in his mid-thirties somehow managed to remain youthful when those around him succumbed to the gradual process of age. He had his brother, his angel, a steady job. Life, for the first time, was good for Dean Winchester.

It became the white elephant in the room. Eventually, Sam had to explain to his children (and his equally dumbfounded wife) about the supernatural, and how Uncle Dean would never grow old and die like everyone else. The day Dean began to resent his immortality was the day his nieces and nephew first looked at him like he was different. Freak, he remembered Sammy referring himself as all those years ago, when he had first heard of his destiny. He couldn't deny the looks of apprehension in their eyes, the ones of sympathy from his brother. Strangers also noticed how the Winchester fellow was supposed to be in his fifties, but didn't look a day over thirty. Initially, this didn't bother Dean. It was nobody's goddamned business, after all. He did his job and he did it well. It wasn't until his younger boss died of a heart attack that Dean finally decided to leave the garage. Hell, if he was human, it would probably be around the time he would retire, anyway.

But the passing of time began to take its toll. The first blatant reminder of that fact was the day Sheriff Mills retired from the Sioux Falls PD. Dean had noticed more strands of silver in her hair than usual when the brothers headed up to congratulate her. Sam had settled down, had fallen in love, married, and had a beautiful baby boy. Shortly after little Dean came daughter Mary, followed by little Charlotte. Dean spent many a weekend teaching his namesake how to fix cars, ride bikes. Tea parties with Princess Charlotte, and soccer practice with tomboy Mary. Young Dean's wedding day, Mary's first day of college, Charlotte's high school graduation. All reminders that life was passing and Uncle Dean, who just wouldn't age, watching it go by in a blink of an eye.

The years continued to pass. The kids had left the nest, started families of their own. Dean's sister-in-law died in her sleep in her late fifties, lung cancer. Sam continued to age, no longer the agile hunter of his youth, his body afflicted with arthritis. His brown hair grew white with age, his face lined with wrinkles and laugh lines. And Dean remained young, looking the same he had over thirty years earlier. At least there was Cas. Dean took comfort in the fact that the angel never changed; he still stared at him with those mysterious blue eyes, he still tilted his head in that funny way when he was confused. Hell, even his dark hair remained in that unkempt style it had been when they had first met. It was familiar, like his father's old leather jacket, or the feel of his hands on the wheel of the Impala.

XXX

Sam died on a rainy morning in late April.

It wasn't how either Winchester had ever thought they would meet their end. One minute he was playfully bitching at Dean to turn down the Metallica, he wasn't a damn kid anymore; the next, he had collapsed on the floor, not breathing. The doctors had told Dean he had died of SCA, or Sudden Cardiac Arrest. But the medical jargon meant nothing to him. All that mattered was Sammy, and now he was gone.

The first day not even Cas could be of comfort. A fury reminiscent of the days after their father had died overwhelmed Dean; the power in his muscles as he swung the tire iron into the hood of Sam's ageing pick-up did nothing to alleviate the anger and grief. He was alone; his brother, the one he had loved, raised practically from infancy, the one he had sworn to protect. No matter that he had died of natural causes (at least, natural according to his former line of work); that there was little, if anything, Dean could have done. Eyes burning with tears, he continued to slam the instrument against the truck, until finally exhaustion overwhelmed him, and he collapsed to the ground, tears streaming along his sweat dampened face.

"Dean."

The familiar voice of Castiel had startled the former hunter. Quickly brushing away his tears with the back of his hand, Dean tried to regain some of his composure. He didn't want Cas at the moment; needed him to get the fuck away. Sure, in due time he would want the angel's company, appreciate it. Hell, the thought of being along actually terrified the hunter. But now, struggling to control his grief, Dean wanted nothing more but the privacy to mourn his brother. Because in a few days, the kids would be coming in from across the country, and Dean would have to pull on the brave face; no doubt be forced to somehow explain how he looked young enough to be his grandchildren's father. No. He couldn't deal with this now. Not when Sam's death was still so fresh in your mind.

"Dean, you're hurting."

No kidding, Cas. Jesus, you'd think after fifty some years you'd start to understand humans.

"Just go, Cas. Please."

Of course, the angel remained standing beside him, and eventually Dean sighed and leaned against the dented hood of the pick-up, gesturing for the angel to do the same. "Fine. Guess it's time for the share and care, huh?"

"I don't..."

"...understand that reference." Dean finished for the angel. At one point, the ghost of a smile would have slipped from the former hunter's lips. But nothing could make Dean smile, at least not now. Castiel merely nodded slowly, stood by his friend beside the truck, staring at the Kansas countryside before him. "He was my friend too, Dean. I'm sorry."

"Yeah..."

"If you need anything, I'm here."

"I'm fine."

"Dean..."

"I said I'm fine!" Another memory suddenly flashed before Dean, of Bobby at Cold Oak, offering him food and comfort in that cabin, his brother lying dead just beyond that little room. He had refused it, brushed the old hunter away. He didn't deserve it, just as Cas didn't deserve his yelling at him now. But Sam had been dead, was dead; and this time, no demon deal could bring him back. And even with his status as Knight of Hell, Dean wasn't even sure he wanted to. Because Sam had been an old man, would have to face his mortality eventually. And Dean, it would be more of the same. Of looking like the same man he had been in 2014, of never again seeing his little brother. Because death was so final now. Sam would enjoy his heaven, and Dean would remain forever trapped on earth, in a young man's body. Sure, there was Cas. In fact, if it hadn't been for the angel, he would have no doubt lost it years earlier.

Castiel observed his friend for a moment, something like sorrow in his clear, blue eyes. After a few moments, in a tone eerily similar to Bobby's all those years ago, said: "You can always call if you need me," and vanished. Dean stared at the spot where only seconds earlier the angel had been, once again picked up the tire iron... and let the instrument fall harmlessly to the ground. Emotionally spent, he finally made his way back to the house, deliberately ignoring the spot where Sam had fallen, the chair still toppled on its side. Feeling a fresh onset of tears, Dean slowly made his way to his bedroom, closing the door behind him... and wept like he had never done before.

XXX

Going through Sam's belongings was going to be hell. The funeral had been a week earlier, and despite pleas from the the kids to go through Dad's things, Dean had purposely put off the task for as long as he could. He just couldn't; to do so would be to admit that Sam was gone, this time for good.

"I know it's hard, Uncle Dean," Mary had told him, balancing her newborn son against her hips. Sammy. Named after his grandfather. Dean, in a surge of guilt, was not even sure he could look the baby in the eye now. "But we'll all be here, if you need us. Dean's go some sick leave at work and Char's going to be done exams in a few days." Dean had refused his niece's offer, saying it was something he needed to do alone. The young brunette smiled sadly, giving her uncle a gentle peck on the cheek. "We're here if you need us," she whispered.

That had been shortly after the funeral. Now, sitting alone in Sam's bedroom, amidst empty boxes and packing tape, Dean felt this weight on his chest, as if he couldn't breathe. He willed himself to sit up off the bed, but this force seemed to keep him rooted to the mattress, Finally, after fifteen minutes of sitting and doing nothing, he buried his face in his hands, giving up. Maybe he did need the kids to do this after all.

"Hello, Dean."

Dean looked up, not surprised to see Cas standing at the doorway. This time, when the angel moved to the bed and sat in a free spot beside him, Dean did nothing to push away. In fact, Cas said nothing, staring at the room that had once been his good friend's, waiting for Dean to talk. He knew the former hunter enough to know that he would talk when he was damn well good and ready; he just hoped that today would be the day.

Sure enough, Dean broke the silence after ten awkward minutes.

"I miss, him, Cas," he whispered, Dean had finally picked up a photo on Sam's dresser, a candid shot of the brothers from around 2007, shortly before the incident at Cold Oak. Dean, leaning against the side of the Impala and holding a bottle of Miller's, is smirking as Sam laughs historically at the joke, head tilted back, still holding his own beer bottle. The joke was long forgotten, but the memory of that day was still etched in Dean's brain. He didn't remember Bobby taking the shot, but the old man had obviously given Sam a copy of the photograph. He had a similar one, the brothers posing for a rare photo op for Dean's birthday. A single tear slid from his cheek, plopping gently on the worn photo.

"It wouldn't be so bad if I wasn't a demon, you know. If I could age like a normal person. Sure, I may end up going downstairs, and I know Sammy had a one way ticket the other way, but at least I'd have a chance, you know?" Dean began to shake as he struggled to control his sobs. "But I can't die, Cas. I'm going to go on for all fucking eternity. And if you did kill me with the First Blade, I'd definitely be going to the pit..." Dean's grasp slipped from the photo; it landed gently on his lap. "I can't do this, Cas. I can't live like this. Everyone I love just keeps getting older, and I stay the same. Lucky me."

"I'm here, Dean."

"Yeah, and I'm grateful for that, Cas. I would've lost it long ago without you. But..." he began to hiccough, tears falling freely from jade irises. "I want my brother, Cas. I want Sammy."

Cas stared at his friend for a moment, looking clearly uncomfortable. Though he had seemed against the idea, the angel was truly afraid that Dean would somehow convince him into finding the First Blade, into letting him kill himself. Hell or not, it would likely be ideal to the demon in comparison to living eternity on earth without his brother. But at that rate, Cas would never see Dean again. He loved him like a brother, and wouldn't be able to go on without him. Slowly, awkwardly, Cas reached for a hug, and was genuinely surprised when Dean allowed himself to be embraced. For several minutes Dean cried in his angel's arms, taking comfort in the awkward attempts at condolences. And when he had finished, he felt a sense of calm for the first time since Sam's death.

"Thanks," he grumbled, slightly embarrassed at his open display of affection. Cas smiled, patted Dean on the shoulder. The two sat in silence for a few minutes longer, until the angel finally zapped out of the room. Suddenly feeling a little calmer, Dean found he had the strength to go through his brother's belongings.

XXX

The days became weeks, and then months. Summer faded into fall, and the first winter's snow began to gently cover the Kansas landscape in a thin, white dusting. Dean's first Christmas without his brother passed, one of the hardest since that one before his demon deal. He had refused to go home for the holiday, unable to face his family as they tried to gloss over their grief with false cheer (for the little ones' sake, of course). Instead, Dean drowned his sorrows in alcohol, frustrated that the drink had no effect. He couldn't even have the comfort of drunkenness. Cas had visited rather frequently, but the angel did little to ease the pain. Memories of Christmases past flashed before his eyes:

"Dad lied to me. I want you to have it..."

"Skin mags... and shaving cream!"

Dean closed his eyes, felt the beginnings of fresh tears form beneath his lids...

...and immediately punched the wall beside him.

XXX

The weeks continued to pass, spring bringing new life to the winter landscape. What a joke. New life. Dean, by this time, had shunned his family completely, occasionally meeting up with his nieces and nephew on separate occasions, but generally avoiding everyone else. The anniversary of his brother's passing brought a new found grief to Dean, and he remained locked in his room, even ignoring calls from a concerned Cas. Dean didn't want sympathy; didn't want the look of sadness in his friend's eyes, or even the attempt at bringing comfort. All Dean wanted was Sam, and he would never see him again.

It was on Sam's birthday when the angel finally dropped in, a familiar looking man in tow. Still dressed in the dress shirt and slacks, eyes just as kind as ever, Chuck stood before him, looking at Dean with kindness.

"Chuck?" Dean stared, dumbfounded at the man before him.

"Chuck?..." the prophet seemed puzzled for a moment. "Aah, yes, that was what I was referred to back then. I'd forgotten." He smiled, gestured to Dean's bed. "May I?" At the nod of approval, Chuck sat beside the former hunter, hands in my lap.

"Actually, Dean, I'm here to help."

"How can you possibly help me, huh? My brother's dead, and the last I checked, I can't exactly meet up with him anytime soon."

"Actually, you can." Dean looked up, a glimmer of hope hidden by mistrust in his green eyes. "Ok, Chuck, I'll bite. Can you bring back my brother?"

Chuck shook his head gently. "No, but I can do the next best thing." Gently the kindly man touched Dean on the forehead; suddenly, an overwhelming warmth rushed through his body, cleansing, intoxicating. He closed his eyes, relishing in the sensations flooding through every vein, every muscle. And when it was over, Dean felt himself needing to grasp onto the nightstand for support.

"Chuck, what did you do?" he asked faintly.

"You're human now, Dean Winchester. I was never the prophet you and your brother believed me to be."

Dean looked up, bewildered. "Chuck, are you..."

"Yes, Dean. I'm God," he smiled. "I had heard of the sacrifices you had made by accepting the Mark of Cain, and how you had fought to retain your humanity following the transformation. I had not heard of it until only recently, or I would have reset the scale, so to speak, earlier. But Castiel has been praying for you. He knows how you grieve the loss of your brother, and wishes that you could become human in hopes of reuniting with him."

Dean had listened to the speech, dumfounded. "Cas, did you?"

"Yes, Dean," the angel smiled sadly. "It pains me to see you like this. I was wishing that you would be able to move on following Sam's death... it was foolish of me to think so. So you are human now, Dean. And when you pass away, your soul will be with Sam in Heaven. The only condition to the deal is that you refrain from taking your own life. You are my friend, and I do not wish to lose you any more than you want to lose your brother."

Dean nodded, still overwhelmed by the whole scenario. He was a human; he could die; and when he did, he would see his brother again. Sam looked at Cas, his angel, and surprised both of them by wrapping his arms around him for an embrace. "Thank you," he murmured, once more feeling the wetness beneath his lids.

"You're welcome," Cas answered, struggling to keep his own emotions at bay. He would lose Dean now. Not necessarily today, but someday. And while he could always see his friend in Heaven, as he had seen Sam, it grieved the angel to know that he would no longer have his best friend, the one with whom he shared that profound bond, at his side throughout eternity. But this was a sacrifice he was willing to make. Anything for Dean.

XXX

Dean Winchester died less than a year later.

One minute, he had been cruising along the highway in the Impala, cranking up the Metallica, enjoying life for the first time in almost two years. The next, he awakened to a warm, summer day, wheat fields gently blowing in a warm, summer breeze. Odd. It's November, he thought to himself, closing the door to the Impala behind him and basking in the warmth of the mid-western sunshine. Curious, Dean continued to follow the asphalt, stopping finally before a familiar looking watering hole, one he would recognize anywhere. The delicious smells of grease and red meat coming from The Roadhouse filled him with a warmth and comfort he hadn't felt in years. He knew by now that he was dead, vaguely remembered the screech of breaks and the crunch of twisting metal upon impact, and felt his heart begin to pound in anticipation. Sam. He was here. He had to be. Grinning from ear to ear, Dean climbed the steps of the bar and gently pushed the door open.

Before him stood an array of people, friends and loved ones long gone. Ellen Harvelle, as beautiful as ever, stood behind the par, a dishrag stuffed in a beer glass. Jo was at another corner, laughing as Ash stood behind his laptop, smirking over something or other. Pamela Barnes, Bobby, Rufus... all good men and women, all long gone, stood before him, smiling and laughing at something or other. All came up to Dean, ready with a hug and a pat on the shoulder. But as happy as he was to see them, Dean's eyes were darting across the bar, looking for the one man he had been needing to see for nearly two years.

Sam was sitting at a corner table, in front of his laptop (the one from earlier, with that skull sticker someone had glued on when Sam hadn't been looking), nursing a beer. He looked just as he had the day they had reunited in Palo Alto, down to the mop of brown hair. He looked up; their eyes met.

"Hey, Dean."

And as Dean found himself locked in the warmth of his brother's bear hug, he finally felt, for the first time in years, truly home.