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“Dean?”
Castiel walked into the dark vault with slow, careful steps.
Suddenly, two arms caught him from behind with a strength even he couldn’t fight. The shock making him drop the angel blade he was holding.
“Well, well, Cas, I didn’t think you were stupid enough to come here looking for me all by yourself…”
Castiel’s heart skipped a beat when he heard Dean’s voice. He had always been able to recognize him, had always felt the presence of his soul every moment they were together. But not this time, this time he felt nothing and that frightened him.
Dean seemed to notice his discomfort and fear and let out a sarcastic laugh, “Oh, c’mon! You didn’t come this far just to let yourself be scared so easily. I thought you were braver than that Cas, don’t disappoint me!”
The angel closed his eyes when he heard Dean’s words. He knew it was the demon talking but even so it was disturbing to hear how natural the cruel voice sounded from Dean’s mouth, as if he had been a demon all his life…“I’ve come to help you, Dean” he managed, trying to make his voice sound as neutral as ever.
“Help me? Really? You?” Dean mocked and then suddenly Cas felt the First Blade touching his neck, pressing lightly but without actually breaking the skin and Dean’s voice hissing in his ear, “I thought you’d come for a quick fuck angel.” Cas’s breath stuttered at the feeling of the demon’s hot breath against his neck, “You couldn’t help me Castiel, even if you were the last angel on Earth; which, by the way, is very likely...”
“I can help you Dean and I will” Cas stated flatly.
With that Castiel dropped his head forward, forcing the First Blade to cut a deep gash in his neck in the same place that Metatron had sliced his flesh to steal his Grace. From the wound started to slip the few glowing tendrils that were all that remained of Cas’s Grace; they stayed suspended in the air, twisting lazily.
Dean moved away from Cas in that moment; the beauty of an angel’s Grace too stunning when seen for the first time through a demon’s eyes.
Cas took full advantage of that moment of confusion, quickly wrenching the First Blade from Dean’s hands. Before the demon could react Cas passed the blade through his Grace and the light seemed to be absorbed completely into the jagged knife.
A growl from Dean made him turn around.
“What the fuck did you just do?” asked Dean slowly, taking threatening steps towards him.
Cas found it hard to speak, he had just given up the last Grace he had left and he didn’t know how long he could stay standing. But the mission wasn’t over, he couldn’t rest. Not yet.
“Dean, if you let me, I can…”
“Give me the Blade” said Dean, not giving Cas time to speak, being without the Blade hurt him, he needed it.
“Dean, please…”
“GIVE IT TO ME!” Dean moved his hand as he shouted and Cas was thrown against the opposite wall of the vault, crashing hard against it. Dean approached his body, now lying on the floor. He was going to take the Blade back and maybe even end the poor, lonely angel…once and for all.
Castiel opened his eyes suddenly and in a flash he cut across the Mark on Dean’s arm with the First Blade.
The scream of pain that was dragged from Dean was agonizing.
The Mark of Cain burned inside of Dean like it wanted to consume him from the inside out. The Grace that had been inside the Blade was transferred to the Mark and both were now fighting inside of him, trying to gain control.
Finally a light rushed out of Dean’s arm, forcing him to close his eyes and making him feel like he was being pushed by an invisible force. When he could open his eyes again Dean looked at his arm. It was bloody and it hurt like hell, but that didn’t matter. Because the Mark of Cain was gone.
Dean felt his head clear of the fog that had been clouding his thoughts since he took on the Mark. He was free from the desires to kill, destroy, and cause pain; he was himself again.
A weak moan brought him back to reality.
“Cas!”
Dean ran to where the angel was still lying on the ground and knelt beside him, his hands clasping the sides of Castiel’s face.
“Cas, no… No, no no” mumbled Dean. He understood what had happened, he knew that Cas had given up his Grace in exchange for his freedom and he knew what that meant.
He knew it, but he sure as hell wasn’t going to accept it.
“Hey, hold on okay? I’ll get you help. I’ll call Sammy, I'm sure he knows how…”
“No, Dean” said Cas weakly, grabbing Dean’s wrist before he could go looking for his phone. “It’s too late. This is how it has to be and it’s okay.”
“No! No, it’s not fucking okay. You’re gonna die Cas! You’ll be gone. How the hell is that okay?!” shouted Dean, trying to keep back the tears.
“Because for once I‘ve done something right Dean, I’ve saved you. That’s good, it’s okay…” Cas replied with a small sad smile as he watched Dean’s green eyes.
Dean ducked his head, tears finally falling and soaking into Cas’s white shirt.
“I don’t want you to go, Cas…” he whispered, fingers tracing over Cas’s face gently.
“I know, and that’s more than I would ever have dreamed possible Dean Winchester…”
Castiel, Angel of the Lord, closed his eyes forever. The human for whom he had given everything was the last thing he would ever see.