It's a rare thing to happen. Castiel is a proud creature, much older than Sam and he used to be much stronger, too. Usually he dislikes being carried. Situations like this are a clear exception, when he's shell-shocked and overwhelmed, when he's reminded that even just scraping his hand and feeling that pain for the first time overwhelmed him not so very long ago.

So he wraps his arms around Sam's shoulders, holds on tight as he's carried inside. Allows the world to narrow down to Sam and nothing else, because that's just what he needs now that his skin is crawling with someone else's touch, someone else's violation.

"Sam," he murmurs, clutches at him harder. At least they're home now. He'll be taken apart and reassembled soon. Everything will be well. Sam's got this. Sam's got him.