I was thinking that too! Like if it was the daemon’s body and not the human’s that angels possessed, the animal’s eyes filling with light, eldritch horrors in its shadow. How much autonomy would the human keep, with their soul suppressed?
Honestly, though, thanks to rory and cat and their daemonverse I just have ALL THE FEELINGS about Jimmy’s daemon trying to interact with Cas and Castiel not knowing how to treat this funny little thing that keeps following him around, and the terrible terrible ways neither of them know what to do. AND THEN CASTIEL FALLS AND I LIE ON THE FLOOR IN A SNOTTY PILE OF TEARS
(I have also novakcested this verse twice, because of course I have.)