Cas’ Death. The sigil is white because, well, he’s dead? And maybe it went stale or something? I actually don’t know. Maybe the brothers finally banished him, metaphorically, and the separation actually kills him? I had like five what-ifs going through my mind during this.
Dean didn’t turn, didn’t look, just stared dumbly at the bare stairwell before him, the stair that went nowhere and ended in a grey, featureless wall. Something dripped slowly from his fingertips. White paint. A banishment sigil was smeared on the wall in front of him, messy, indistinct.
Cas stepped toward Dean. His shifting weight made the wooden stair beneath him creak. Dean twitched, but did not turn.
“Dean,” Cas repeated more firmly. “It’s me.”
Dean’s shoulders shook slightly, and he made a noise somewhere between a scoff and a sob.
“Come and get me already,” he spoke after a time. “If you’re gonna.”
Cas had never heard Dean’s voice sound so smooth, so small, like all his willfulness and struggle had simply drained away. He sounded almost angelic.
“What are you—“ Cas was close enough now to see the tight lines carved under Dean’s eyes, around his mouth. And yet Dean still did not turn toward him, his shining eyes instead fixed on something at his feet, something only he could see.
Cas placed a hand on Dean’s shoulder, fingers briefly touching where his seal once blazed, and finally, finally, the man moved—in fact, Dean flinched back so violently Cas was immediately worried he might slip on the stair and fall.
“Cas?” he whispered, voice ragged, raw.
Dean collapsed in on himself then, shoulders hunched, eyes wide, panicked. He clutched his paint-covered hand as if it were wounded. He stared at Cas, then the ground, then Cas again, finally at the white paint on his hands.
“You’re alive,” Dean choked.
“I am.” Cas did not try to touch Dean again.
“But you—“ Dean gestured wildly at the bare floor before him. “No. You’re. I saw you—“
“It’s this place, Dean.” Cas held his voice steady for Dean’s sake. Somehow, knowing that was the reason made it easier to do. “It plays tricks on you. What you saw was an illusion, nothing more.”
“But your—wings.” Dean’s hand twitched, as if he wanted to lift his palm and brush it against Cas’s feathers for himself. Instead, he clenched it into a fist and pounded it once, lightly, against his thigh. “One was ripped right in half. I saw it. See it. Right there.”
Cas flexed his wings reassuringly. Battered, yes, and a little bloody, but still whole.
Dean peered at Cas’s wings, watching the feathers ruffle with naked suspicion. “Okay. So how do I know you’re the one that’s real, and he’s the illusion?”
Cas fought back a smirk. It was uncanny how familiar all this was. The years had aged them both, but Dean was still the same righteous man Cas met in the Pit; his clever mechanic’s hands stained with blood, his human soul burning as brilliant and beautiful as the sun.
Moving slowly so as not to startle him, Cas leaned in close. Once more he rested his hand on Dean’s shoulder. This time, Dean did not flinch away.
“Because part of you calls out to me, Dean.” Cas hand lay on Dean’s shoulder, not squeezing, not pushing. Just touching. Waiting. “It will always know me, the real me. It will always find the way.”
Dean let his fist unclench at last. Relaxing slightly, he began to lean into Cas’s palm, the barest resistance.
“Right,” said Dean, drawing a shaky breath. He gave the empty stairwell one last, haunted look. “Right.”
“Come,” said Cas, dropping his hand. Dean swayed a little, as if he’d lost his footing. “They’ll be here soon.”
“Wait.” Dean swallowed. “How do you know I’m not an illusion too?”
Cas allowed himself one small, secret smile.
“Don’t ask stupid questions, Dean,” he said as he walked away.