The touch was unexpected, Dean could rationalize that it was because he didn't really see Cas move. That in itself wasn't so strange. Thankfully, he didn't jerk, and that probably said a lot for how comfortable he was with the angel, despite everything. If Cas wanted, he could kill Dean with a touch. He'd seen him do it to things a lot more powerful than Dean. He smiled a little more, but maybe more soft when he spoke, the low timbre of his voice strangely relaxing.
He had to wonder, just how often he dreamed of Castiel, just as someone in the background. He was pretty sure he was featured in a helluva lot of them, but they usually weren't nice. Then again, it felt pretty rare that his dreams were nice, in the usual sense, anymore.
Some part of him just wanted to touch, and that was nothing new. He flexed his fingers at his side when he felt Castiel grip his shirt. There was probably no hope for trying to imagine why the angel was doing that. He usually only understood things after the guy explained and he'd sat on it a while. "Angels?" He offered, trying to push down the urge to move. So close, and still so far. It probably would have been laughable if it didn't have an edge of pain to it. "You can pop in my dreams. Been a while since I went fishing in there, though."
He tried for a smile, but it didn't quite meet his eyes and he closed his eyes for a moment before shifting, forcing himself to try and seem casual, even if Castiel might not pick up on it as he reached an arm across him, hand on his back to urge him in closer. "Comere." If he didn't look, it might be enough to make it feel okay.