Castiel feels lightheaded and weak when he sees. His legs give out and he leans his shoulder against the wall to prevent himself from falling to the ground. The weight of the knowledge of what had happened is like a car smashing into a glass house. He stares at the floor before him, unable to look up.
"Cas, look at me,"
He can't look up.
"C'mon, man."
He can't.
Sam places a hand on Castiel's shoulder and the angel turns towards the younger Winchester even as he feels Dean's gaze on him. He cannot look at Dean. Sam 's brow is furrowed and his eyes are still red-rimmed. "Cas, I, uh… Do you want me to stay?" Sam asks under his breath, leaning closer to Cas so his brown eyes can take in the angel's shell-shocked face.
Castiel shakes his head and mutters, "No, Sam. I would like to speak to Dean alone."
Sam purses his lips and nods. He straightens to his full height and looks at his brother, eyes growing sadder. "I'll be in the kitchen making coffee," he says, jerking a thumb in that general direction.
"Yeah, okay," Dean's voice is quiet from behind Castiel's shoulder and Sam walks out of the door quietly, leaving Castiel alone with Dean.
Castiel takes in a deep breath and turns around. He looks at Dean's boots and tries to steady himself. He wants this to be a nightmare. Some kind of trick played by Metatron. He wants Dean to laugh and pop off about how this was a colossal prank. Anything but this.
"Cas, please," Dean's voice is wrecked and it stirs something in Cas, causing his heart to ache.
Cas looks up. His heightened vision sees inside of Dean and it's like he's peering into a deep, black pit and it's so unlike Dean that Castiel staggers back with a sharp gasp. Then, he sees it. Dean's soul. The bright, white light that holds its own with the brilliance of angelic grace, still fighting—still shining—amongst the black tendrils of darkness that now reside in the eldest Winchester. Castiel focuses and sees Dean's face. And it breaks his heart. Because he sees the pure terror in Dean's green eyes. And it's so strange an emotion to see on the man. He's never seen Dean so scared and lost.
"Dean," Castiel says softly, eyebrows furrowing in concern.
"Cas, you gotta help me. I-I can't be this." Dean's voice is tight and Castiel knows the hunter is holding back his emotions.
"We'll figure it out. We just need to—" Castiel starts, but Dean steps forwards so suddenly that Castiel stops.
"No." Dean's jaw is set. "We can't wait… I don't want to be this. I don't want to get worse." He stops and runs a hand over his face as he turns away from Castiel. "There has to be something you can do to…"
"Heal you?"
Dean frowns and laughs humorlessly. "Not exactly, Cas."
Castiel's breath hitches in his throat at what Dean is implying. He hesitates before walking around so he and Dean are face-to-face once more. "I did not fly through the depths from Hell, rebel, fight my brothers and sisters, and destroy the angel tablet only to destroy the one man I did all that for." Castiel says firmly, but tenderly as he tries to catch Dean's downcast eyes.
"You don't get it," Dean sighs. "I'm not that guy anymore… Hell, I'm not even a man anymore. I'm not worth saving, I never was."
Castiel shakes his head and opens his mouth to argue when Dean interrupts, "Look at me, Cas. I'm the kind of monster we hunt. So do. The damn. Job."
Castiel looks up and Dean's green eyes have been swallowed by the blackness that is infesting his insides. It's startling and unsettling and painful even to see Dean this way. Castiel stands up straighter, looks Dean square in the eyes and says, "No."
"Don't be soft. Do it." Dean says in a huff, he's shaking and Cas can't tell if it's from anger or trauma.
"No, Dean." Castiel steps closer to Dean and gently holds the Winchester's arm.
"Kill me, Castiel." Dean says, voice softer, the black in his eyes receding and expanding irregularly as though he's struggling to control it. "I know you can do it."
"I can't. And I wouldn't if I could." Castiel murmurs.
"Dammit, Cas," Dean says, voice breaking before he wraps his arms around the angel's torso and buries his face in the crook of Castiel's shoulder and neck. Castiel reciprocates the hug, wrapping his arms around Dean and rubbing the man's back and shoulder blades soothingly.
"We'll figure this out, Dean." Castiel softly repeats his previous promise into Dean's sandy blonde hair. "I'll save you."
