Author's Note: I'd like to thank Ranisi123 again for beta'ing this chapter.

CHAPTER TWELVE: The King Has Fallen

The tentative knocking on Castiel's door is what snapped him out of his daydream, Dean's cold, ruthless eyes still haunting Cas' every waking moment. Shaking his head to clear it, he stood up from the bed causing a slight creak.

The angel opened the door, a scowl on his face when he saw who the knocker was.

Giving him his signature puppy dog eyes, Sam shrugged sheepishly. "Cas, I'm sorry." But, Cas wasn't Dean, so the puppy dog eyes didn't mean shit.

"Did you mean it?" Castiel questioned, his voice filled with sorrow instead of anger. He furrowed his brows in curiosity as he watched the confusion cross the hunter's features.

"Did I mean what?" Sam crossed his arms, waiting for the angel to elaborate.

Leaning against the door frame, Cas looked at the youngest Winchester with pity. "When you said you wouldn't save Dean? You really did mean it. I can't think of any other reason you would just give up on him."

"I wasn't the one who gave up, Cas. He did when he took that fucking Mark!" The hunter yelled, his voice gruff. "Nobody asked him to take it and nobody asked him to hide how bad it was affecting him! But, because his answer is always 'I'm fine', nobody ever knows how bad it really is!" Sam was shaking with anger as he took deep breaths, trying to calm himself down.

"Who told him that you weren't brother's anymore, Sam? Who told him you wouldn't save him? Did you really not see that you are his whole world? That without having you as a brother, he had no one to protect?" Cas scoffed. "That was all he was living for; to protect you." Cas pressed his lips to form a thin line. Deciding he wasn't able to even look at the young hunter anymore, he slammed the door in his face.

Running a hand down his face tiredly, Sam blinked away tears as he retreated to his bedroom. The youngest Winchester knew Cas was right.

This was all his fault and he couldn't save his brother.

….

"There. Your precious angel is home safe and sound. Mind letting me go? You're wrinkling the fine Italian." Crowley quipped, grasping the Knight's wrist.

Dean lowered the King to the ground but left a firm hand on his throat, not trusting him. "You said there was a way that I couldn't be cured. Spit it out." The hunter growled, black eyes never leaving the former crossroads demon's face.

Crowley chuckled, amused at how well he can manipulate the eldest Winchester. Beckoning him forward, he grabbed Dean's head and yanked it forward so the King's hot breath was tickling the Knight's ear.

As Crowley spoke, Dean could feel himself getting more and more enthusiastic about the plan. Smirking, the Knight pulled away once Crowley had finished.

"Wow, Crowley. You were actually helpful." Dean paused, a cruel glint in his eyes. Finally letting go off the King, Dean picked up the First Blade from where he had dropped it on the floor, welcoming the rough feel. "It's a shame I still have to kill you."

Crowley looked at what was supposed to be his Knight with betrayal and bewilderment as if he hadn't expected this turn of events. "After I just helped you? Squirrel, trust me you don't want to do this." The King's voice was desperate as he tried to sway Dean.

The Knight chuckled darkly as he watched Crowley beg for his life with sweat dripping down his chin. Dean would bet anything the former crossroads demon never actually expected to die.

Guess he was wrong.

Dean's dull green eyes switched to black as he rested the Blade right over Crowley's heart, applying light pressure.

The King squirmed slightly before Dean slammed his left hand on the wall right next to his face, closing in to where his nose was almost touching Crowley's. "I could take my time. But instead, I'll let you off easy and just slide," The Knight said 'slide' with pure pleasure in his tone, "this in real quick. But if you fight it, well..." Another sinister chuckle left Dean's lips as he continued. "Then I'll chop off anything that dangles and then kill you."

"I love when you talk dirty. Touches me right where my bathing suit goes." The King quipped, trying to hide the fear in his voice. He cleared his throat as he saw the blood-lust in the eldest Winchester's eyes as well as the lack of humanity.

What the hell did I do?, the King thought as he stood up straighter, ready to meet his death.

"Keep joking. But for once, Crowley, you're not getting out of this." With one last smug smile, Dean felt the raw thrill of his blade breaking flesh, meeting bone, and then piercing the heart.

The King's eyes and mouth flashed a bright white light as the former hunter twisted the jawbone for good measure, with a malicious smile plastered on his face.

With a yank, Dean pulled out the First Blade and watched as Crowley's lifeless body fell to the floor in a heap.

Before having time to relish in his accomplishment, the Knight felt a sharp twist deep in his gut, the pain bringing him to the floor. Dean's eyes widened in shock as he coughed, his hand covered in crimson.

The eldest Winchester's head took a sharp turn to the right and back to the left before he squeezed his eyes shut, now on his hands and knees. The veins around Dean's eyes and leading up to the Mark of Cain turned scarlet, leaving dark tendrils going up his arms.

Malevolent laughter reverberated off the walls as Dean stood up, eyes black.

Except this wasn't Dean.

It was the Mark.

After killing Crowley, the Knight felt a change in his soul. The past week or so, the Mark had been gradually losing its grip on Dean, his humanity breaking through the cracks. But now, the Mark had completely taken over the former hunter.

The Knight's eyes flashed a blood red before switching to black as he picked the First Blade back up, a wicked grin creeping across his face.

With one last proud glance at Crowley's dead body, Dean disappeared from Hell with a new objective in mind.

….

TBC

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