In season four of the show Supernatural, an angel named Castiel is introduced after it turns out he pulled the character of Dean Winchester out of hell. Description from toptenz.net. I searched for this on bing.com/images
He is a badass in some respect, but after about season, well after he made the deal with a crossroads demon we definitely see that strong co-dependency thing between him and Sam. And from there to the point Cas drags him from hell he and Sam are slaves to each other because well they're each others weakness!