It is. It's a bit like when you sell your soul to the devil, except that in this case, you're linked with your boss (like a henchman to his mobster's "godfather").??
I don't think I know what an "âme damnée" is, but it sounds like a "soul that is damned (to hell)". It must be an idiom ?
Ok... I'm not so sure the word here is henchman then, because it seems to me that the "âme damnée" has no choice in the matter whereas a henchman does.Une "ame damnée" is somebody devoted to another person who uses her/him as a tool for dirty work (killing, robery, etc).
Wouldn't do, I'm afraid. In this case, a very charismatic female "godmother" owns a brutal sadistic henchman who is capable of anything to please her. He is not exactly "forced" to obey, but the result is pretty much the same.
How about combining them ? I don't really know your context, but what about "That bastard owns me. I'm nothing but a pawn in this twisted game he's playing".