Supernatural, the TV drama horror series phenomena is now well into its fifth season in the US and a bonafide hit all around the world making stars of both Jared Padalecki and Jensen Ackles who play brothers Sam and Dean Winchester respectively.
An awesome artikel I found on LJ that uses a compilation of interview evidence which shows why Castiel's loyalty is not an issue. No spoilers beyond aired episodes in Season 5.
From Supernaturalwiki:Cosplay - dressing as characters in the toon - has been a minor but creative part of the fandom. Press on the red linken so u can see some hilarious pics of fans dressed up as SPN characters!!