A/N: This is the first fanfic I've ever written for this fandom. Review, favorite or whatever~ tell me what you think.

"Dean, stop it!"

It was too late, he knew.

There was nothing he could do at this point. Castiel watched as the eldest Winchester pushed his wooden weapon through his little brother's throat. Sam gagged and garbled, and all while looking into his brother's black eyes. He fell to the ground with a soft thud. His eyes stared up blankly and his mouth moved.

"I forgive you," was what was left unheard.

The life fighting in him finally gave out and Sam's body went limp. Castiel stared down at the body. His eyes were still open and gazing up at the angel and the monster who slew him. Cas felt to the need to close them. Even though Sam was dead, Castiel felt that he shouldn't see this. He made a move to do so, but the demon before him blocked his path. A wicked smile spread across his face as he felt his little brother's blood drip off of his fingers. He brought the hand up and flicked his tongue across the liquid.

"Mmm," the demon let out a blissful moan. "Delicious, Sammy."

Castiel's fists clenched and shook at his sides, blue eyes glared daggers at him.

To think that he and this monster were snuggling together on the hood of the impala, laughing and joking his brother, sneaking quick, sweet kisses during hunts, and making love during the night only days before this. Everything had been just fine until they took on this hunt.

The hunt that spurred the Mark of Cain on to the point of no return.

-DestielSpn-

Dean had found a case that struck a little too close to home for both him and Sam. Women were spontaneously combusting in their homes. Their bodies were burned in front of loved ones despite their attempts to put out the flames. Castiel held on to Dean's hand while he explained the case to his brother. They both held grim expressions on their faces. "It's obviously the work of a witch. We just need to find hex-"

"I frickin' hate witches," Dean growls clutching back on the angel's hand.

"It's only two hours away from here," Sam said, rolling his eyes. "Get suited up so we can go. You too, Cas."

The Winchesters, plus Castiel, drove to the police station, spoke with the victims' families, and quickly collected the hex bags from their houses. Castiel easily disposed of them . Sam located the witch's next victim, a young bartender ("She makes glasses filled with heaven, Cas. This just got serious." "Dean, I feel that I should be offended by that.").

The boys went in the woman's apartment with their guns up and defenses on tight. The "witch" was an elderly man with a crooked yellow smile. He'd already killed the bartender, much to the hunters' dismay. The brunette's charred remains were stashed in a corner in her kitchen. A hex bag was snugly tucked in her hand.

"It was her... my daughter. My daughter dies again," the old man cackled and turned to stare at the Winchesters. "She burn-"

"That girl was not your daughter!" Sam shouts at him.

The crazed look he giving turned strangely turned lucid. His eyes went black and the yellow smile seemed to go impossibly wider. "Momma Crowley has told me differently, did you know that boys?"

Castiel started after the witch-turned-demon, but he was stopped by a few of his companions. They grabbed onto his trenchcoat and yanked him back. One of them held an angel blade to his neck.

"I suggest you cooperate, Winchesters, or this angel dies." The elderly demon threatened.

They slit Castiel's sternum just to prove his point.

Sam dropped his gun, Dean didn't.

Castiel could see the change in his lover's eyes coil.

It tightened the more the man spoke.

He didn't listen to his brother attempt to negotiate with them.

Nor did he bother to pay attention to Castiel's calming words.

"Everything will be alright, Dean! Calm down!"

Dean's eyes changed from their usual emerald to deep charcoal.

"Let him go and get the hell out of here. If you don't, then I can't promise your safety," he says, smirking a bit.

Castiel's captors laughed at him.

The one holding angel blade put a quick slice on his arm, making the angel groan angrily from the pain.

"You... don't say I didn't warn you," Dean steps toward the elderly man.

"Don't do it, Dean! Sam, stop him!" Cas ordered the younger.

Sam yanked his brother back, but was stopped by a strike to his face.

"Hahaha!" The demons' laughter rose.

"That's right, get angrier, boy. Feel the mark take over, become one of us," they spurred him on, making his anger rise with each step he took.

Castiel shouted at them. "Be quiet! All of you!"

The demon holding the blade dug the weapon a little deeper into his skin, effectively silencing him.

A flicker of black came in Dean's eyes.

He reaches into his back pocket.

"Do you believe you can sto-"

Everyone stopped. They all stared with wide eyes as Dean clenched his fist around the elder demon's neck. With a flinch, the demon was stabbed in the neck with, what Cas could see as, the first weapon. Its head barely hung onto his body.

The apartment was silent, eerily so, and the foul noises of its death could be heard by them all. What shocked them further was hearing Dean's laughter as he tossed the corpse aside.

"Who's next? Huh? Maybe you with blade?" He started for Castiel's captors. "Wanna play?"

The demons let go of Castiel and set up their defenses.

Dean slew them all, brutally striking and stabbing them. They were all dead within a few short minutes.

The Winchester's bloodlust didn't leave him. In fact, when turned to his brother, the mark on his arm glowed a dark red hue.

"Those guys weren't that much fun. C'mon, Sam, it's your turn,"

Sam's eyes widened. His knife was tucked away in the trunk of the impala. Now, he had to try to subdue his brother with his bare hands. Castiel heals his own wounds and tries to stop them.

"Don't worry, Cas. I'll stop him," Sam said, looking back at the angel with a confident smile.

Little did he know, those would be Sam Winchester's final spoken words.

-DestielSpn-

Castiel replayed Sam's death and got angrier each time he saw Dean's blade rip out his throat. He thought back to the promise he'd made to Dean because now would be the time to fulfill it.

"Cas, promise me that if I ever go dark side again, you take me out."

Then he remembered the kiss they shared afterwards.

"You'll be fine, it won't happen."

Did he have to be so naive? If he'd taken precautions, researched a bit more, and stopped being so damn optimistic then maybe -just maybe- he could've prevented this. Sam would still be alive and they all would still be together and searching for the cure. That time was over and now one of them had to die.

Dean walked until he and his angel were nose to nose, picking the forgotten angel blade from beside a demon corpse.

"C'mon, Cas, you don't wanna do this," he teased.

"You're right, Dean. I don't want to do this."

Dean turned the blade towards him. "If you don't kill me, babe, then I'll kill you."

Castiel's heart clenched in his chest.

He didn't want to die, nor did he want to kill Dean.

To hell back he'd been for this one man and he'd happily do it again.

This one man -his righteous man- gave him the strength to fight his battles with his head held high because, in the end, he knew that he would have someone to come home to.

Now, his heart struggled to make a decision.

No matter what he does, his family won't ever come back together again.

"Dean..." Castiel croaked, tears welling in his eyes. "I can't do it."

The demon arched an eyebrow at his angel. "Are you serious? You're not gonna put up a fight?"

Castiel shook his head. "I can't bring myself to hurt you. Don't make me do it."

Dean plays with the angel blade in his fingers while wearing a disappointed pout.

Cas steps closer to him, softly pressing his lips onto Dean's.

Dean's eyes briefly flickered from green to black. Pain shot through him and he shoved the angel away. "That... Whatever you did..."

"I'm sorry I couldn't save you," a sad smile spread on his face.

Dean places the tip of the angel blade at Castiel's chest.

"I'm beyond saving, Cas. It's not like I would've appreciated it anyway."

Castiel steps closer, letting the weapon puncture him just a tad.

"I love you so much, Dean."

The pain came back more viciously than the last strain. Dean growls at him, pressing the blade in a little more. "Stop it!"

"I'll miss you-"

Dean gives the final thrust, eyes completely fading back to their original hue.

He watches the life leave his angel with the tears his demon was holding finally releasing themselves.

"Goddamn it, Cas!" He shouts, tightly holding the limp body close to him.

His fingers run through Castiel's dark hair and lightly sets him on the ground.

He turns around.

A few feet away, his baby brother's bloodied body lay spread out on the ground. His eyes were still wide open.

"Sammy..." He slid to the ground next to Sam's corpse, finally shutting his eyelids. "I'm sorry you had to see that,"

-DestielSpn-

Dean sat on the ground with Sam and Castiel's bodies for four hours. He whispered loving words and apologies to them. The tears stopped falling after awhile, but he felt like shedding gallons more.

"I knew this was coming, guys," he says, voice raw and hoarse. "But, I told you to take me out, Cas! Why did you just sit there?!"

"I love you so much, Dean."

"If you really meant that, you should've killed me! I don't-no, screw that- I can't live like this." He chokes on his words. "Without you or Sam... You guys were all the family I had. You can't leave me like this."

"I'll miss you."

"I'll miss you, too," Dean stands up, taking Castiel's body in arms. "Let's go guys."

-DestielSpn-

Sam's body was the first to burn on a stack of wood. Dean's lighter shook in his hands. The moment the flames ran over his brother, all of his memories of him came back to him. The day Sam came home, his first steps, the astonished look in his eyes as he stared up at fireworks, scratching their initials into impala, and even the day he went off to college played before him in his mind. He forced all of the bad memories away for his own sake, knowing they'd eventually lead up to what had happened only hours ago.

Castiel was next, before Sam's body melded with the ember. Dean stared at him for a good ten minutes before he able to throw the flame. He could still see the dried tears on the angel's cheeks. Castiel had cried and begged him... Not to allow him to fulfill the promise they'd made long ago. Now, the angel he'd loved so much was gone. Dean stood in front of Castiel, his mind drifting back to all the good memories the two of them had shared. Castiel was a Winchester, even without the blood, and Dean was proud to have been pulled from the depths of hell by him.

Dean started the lighter up again.

There was one more family member to say goodbye to.

He reaches into his pocket and pulls out keys.

A shuddered sigh left him as he softly kisses them.

They were tossed into the impala, his baby, without a second thought.

Next came the flames.

The car, the one that's seen it all, shared the same fate as his brother and lover.

Now, there was no family left for him.

Since there was no one left, there was point in having passenger seats.

His back turned on all three flames.

He takes a deep breath and walks forward.