Crowley's face scrunches up at that, because a tree being the source of all creation doesn't quite scan for him. A tree being the mother is definitely wrong.

Still.

"Right," Crowley says. "That tree. So. Apparently, all things return to the tree at the end of their life. Somehow, though, the tree also wants to... absorb us right now. Maybe because we don't belong here? Little bit fuzzy on that. Anyway, that is apparently the reason we have to wear the bracelets. So, I tell Odin to just take them off. Don't believe him on this 'wear it for your own good' business. Next thing I know, I'm discorporated and feel like something is trying to unravel me."

Maybe that's not a good explanation, but it's what it had felt like. Like he was being unravelled, slowly being unmade again into nothingness.