Sam just stared at him, torn between devastation at losing Dean and relief about Cas not disappearing as well. He was unfamiliar with this feeling, the feeling of his brother simply disappearing; every time he'd lost Dean before, it was because something horrible had happened to him. Because he'd died, or gone to hell.
Well, he thought vaguely, if Dean had gone back to his original point that he'd come from, technically he was going back to go to hell. "I just... I just do," he said. "If you can't find him, then he's gone, right? It was a second ago that he disappeared on the phone, and nothing could get him out of your reach that fast. Except the tesseract. But I knew it-- really, I knew what had happened the moment the call cut out. I just didn't want to believe it."
He felt strangely separated from what he was saying, like he was watching himself explain but wasn't actually doing it. Fuck, he needed to pull it together. Except how could he? Dean was gone.
"Can we go back-- can you take me back to the apartment?" He needed to see it, suddenly. Needed to see the phone on the floor, Dean's stuff all around, but his brother nowhere to be found. Unless his stuff disappeared, but that didn't happen when people got pulled back, right? They put people's things into storage. They wouldn't be putting Dean's things anywhere, though; Sam would shoot them if they tried.