1) Is your character a spirit? whoops probably should have filled this out before tagging you... but ehhhHHHHH shh shh waves hands, ANYWAY, as you know cas is an angel who got his mojo sucked out. there's still some kicking around in there, enough that he's able to sense weird shit but not do anything useful really, so do with it what you will! i leave it in your capable hands.

2) Does your character have a high spiritual sense? well he definitely doesn't have massive amounts of energy anymore, and what he has definitely isn't dark, so i would say... nnnnooo?

3) Are you comfortable with Rei getting a read on your character should they meet in person? absolutely! go wild, do whatever you like, truly, i'm easy. have fun with it!