Disclaimer: I do not own Supernatural, and after this, I'm glad I don't!
It was his fault. All his fault.
It's not like he wanted to, of course. Who sits down and plans to murder their best friend and his daughter? That's just sick.
He's just sick.
No, he's worse than sick. He could have prevented this. He should have known what he was getting into. So what if he didn't want to? He had wanted the Mark, and now it controlled his every move. Yeah, it burned insatiably and throbbed uncontrollably, and maybe the only way to stop it was to give in, but he had thought that his father had raised him to be more of a man than that.
Every time he lost control, it got a little worse. Cain had been right all along, and there was nothing they could do to change it.
Dean forced himself to open his hand, and the First Blade clattered to the ground, the only sound in the building. He had killed Crowley without the blade easily enough; after all, demons are still the thing he hunts. The death of this demon, however, jumpstarted the psychopath he had been containing for so long.
Suddenly, he would fall asleep at home and wake up kneeling in the middle of absolute carnage. He was constantly fighting to control the Mark, and he couldn't let his concentration slip for a moment. All he could think about was what Cain had said.
It was like flashing back to when his father had died, or when Michael had wanted to possess him, or when the Croatoan virus had broken out in the real time period.
Dean moved his hand to his belt slowly and wrapped his hand around the handle of his gun.
All those times, he'd been told he would have to kill Sam, but he never could bring himself to do it. Over and over, no matter what the price, he would always pay it to keep his little brother safe.
Collateral damage was unavoidable, but he refused to let Sam be part of that.
As the burning had gotten worse and he had had to be chained up in the dungeon at night, he had thought about his role in his brother's life more and more.
Fresh tears spilled over his cheeks, tracing the same salty path, as he moved his left hand in front of his body and grabbed the gun tightly with both hands.
He knew he couldn't control the Mark, and he knew he could never live with himself if he followed what Cain had said. He didn't have a choice. He had already gone too far. Nothing else in the world was worth his brother's life.
Nothing.
He had grabbed his gun, but he only took one bullet. His arm was aching horribly, but he had kept the grimace off his face walking past Sam. Then he'd stopped. He was never going to see his brother again, no matter what happened, and he just couldn't leave it like this.
"Sammy," he said in a low voice without turning around.
"Dean? You okay?" Sam immediately responded, worried.
Dean took a deep breath and slowly turned around, repeating his own words from what seemed like a lifetime ago. "You know there isn't anything I'll ever put in front of you, right?"
Sam was instantly on alert. "What are you doing, Dean?"
"You know that, right?" Dean insisted, avoiding the question.
Sam nodded, his face softening. "I know, Dean. And you know there isn't anything in my life more important than you," he answered, realizing that his brother needed to be reassured, not stopped.
Dean nodded and then stepped forward and pulled his taller brother down into a fierce, brotherly hug, barely relaxing when it was returned wholeheartedly.
"Sammy," he pulled away and caught his startled brother's eye, "I'm a monster, man. Even you have to see that!"
"We're going to fix it," Sam answered with obviously false confidence. "It's going to be okay, Dean. I'm not going to let you die a monster," he promised.
Dean blinked back the looming emotion and ignored the voice in his head protesting that this problem couldn't be fixed. The voice was wrong. "I know you want to help, Sam, but this one's on me," he tried for the umpteenth time. "You have to focus on helping people, and I have to focus on not hurting them. That's just the way it is, okay? If I close my eyes for too long, I'll be surrounded by a massacre when I wake up. You have to understand that you aren't safe around me." He had meant to stop after the second sentence, but he couldn't.
Sam shook his head emphatically. "No, Dean. You won't hurt me. I'm not leaving you. We're brothers, man. I'm not letting anything hurt you, including yourself, got it?"
Dean nodded, hating himself for rambling on like that. "I'm going for a drive while the air clears up. Smells like a chick flick moment in here, man."
Sam smiled guardedly. "Be careful, Dean," he warned.
Dean opened the chamber of the gun and dropped the single bullet onto the ground. He didn't need that.
It should have been an impossible choice. It spoke volumes about how screwed up his family was that he made the choice without a moment's hesitation.
He grabbed his phone and pressed redial.
"Dean?"
"Cas, where are you, man?" Dean asked.
Castiel mentioned a restaurant name, and Dean gingerly pulled Baby onto the main road in the direction he had to go.
"Okay, do you have the First Blade?" Dean asked.
"Of course," Cas answered, clearly confused. "Dean-"
"Just hang tight then, okay?" Dean asked.
"But-" Cas began to protest but Dean hung up and turned off his phone.
Once Cas realized he couldn't reach Dean, he would probably call Sam, giving Dean about fifteen minutes total to do everything he had to.
Dean rolled the gun over in his hands slowly, reluctant to let it go. It was like a lifeline: the last connection to who he used to be and what he used to stand for. He let it go with a sigh and winced as it hit the ground. That's when the front door opened.
He had weighed out every possibility, and this was his only choice. He had to have it done before Sammy got there. He refused to put Sam in danger, and if that meant that Cas had to be in danger instead, then that was how it would be.
He pulled up in front of the restaurant, a little burger joint, and walked in to meet Cas before realizing why Cas had sounded so hesitant.
"Claire? Cas, give me the blade and get both of you out of here, okay, man?"
Cas shook his head emphatically. "Dean, I don't know what you're planning, but Sam and I are both very worried," and that was as far as he got before Dean closed his eyes. Sam was already on the way. There was no time to waste, even if it meant killing Cas and everyone else in the building.
***SPN***
Dean slowly looked up from the two weapons on the ground to Sam's concerned face. Concerned, not horrified or scared or disgusted.
"Sammy," Dean's voice broke, "you aren't supposed to see this, man. Get away from here."
Sam looked at him incredulously. "Did you not hear me earlier, Dean? I'm not leaving you. So what if you end up hurting everyone else? Don't you know you're the only one I care about here?"
Dean dropped his head and whispered, "Cas?"
Sam laid a tentative hand on Dean's shoulder.
Dean immediately jerked back, fighting back the demon. "Sam, back up," he ordered.
Sam tightened his hold instead.
"Sam! I don't want to hurt you, man!" Dean begged, sobbing.
"You aren't going to hurt me, Dean," Sam echoed. "We're brothers, man. We're family. We can beat this, but I'm not letting you do it alone."
The Mark burned and throbbed, and Dean couldn't stand the proximity of the Blade and its next target anymore. Against his own will, his right arm reached for the jagged piece of bone.
Sam noticed and knelt down, his intensity growing. "Dean, you're better than this, man. It's going to be okay. You can fight it," he insisted.
Dean shook his head as his fingers touched the blade. "I'm sorry, Sammy," he whispered, raising his arm. Sam didn't move. "Sam, get away from me," he begged, but his brother just sat there, practically in his lap, as the blade moved closer and closer. "No, Sammy, please, get back, man. I can't do this! I can't let this happen! Sammy!" His arm kept moving, and he fought in vain to regain control as his worst nightmare played out.
"It's okay, Dean. You won't hurt me, man," Sam answered evenly, breaking Dean's connection to the Mark for the split second he needed to change the direction of the blade before the Mark took over again and gave one final thrust.
Sam screamed in pain as the blade pierced flesh and blood began to pour out of the mortal wound, but Dean smiled faintly even as the strength melted out of his body.
"Dean! No, what did you do? Dean! Cas! Dean!" Sam screamed over and over, holding his brother tightly and rocking back and forth. Finally, he knew that Dean was… at peace. His shoulders shook harder, and he choked on the sobs that all fought to break out at once.
"Why did you do it, Dean?" he begged through his tears, knowing that he wouldn't get an answer.
Dean's spirit stood beside Death, watching his brother for a moment before accepting Death's outstretched hand. As his unmarked right hand met Death's he heard Sam's final question and pulled back slightly, pooling all of his spirit-juice for one last thing.
"You were right, Sammy," he whispered, flickering in front of his brother and grabbing his attention. "I could never hurt you," he admitted, holding his brother's tearstained gaze for as long as he could before joining Death.
He didn't care where he was going. Anywhere without Sam was hell, but everywhere, knowing Sam was safe, was heaven.
Death cocked his head as if listening to something. "Dean Winchester? You took care of your brother. Your father is proud of you."