I have a theory about why Crowley sits in his chair like this. It’s a defensive instinct to protect his stomach. Not only can he easily jump backwards if those he’s speaking with lunge at him, but he’s separated himself from them by the chair’s wooden back.
It’s to leave space for his wings.
Ding ding ding We have a winner^^
I mean do you have any idea how much red tape it takes to revive a Winchester - again?