Any
It's tough to come up with a vampire-Renfield relationship that doesn't devolve into Arte Johnson scuttling around for George Hamilton's Dracula, but one that occurred to me this morning (thanks to the Facebook group Comics Out Of Context) is Batman and Alfred.
(I might have read it before but I don't remember it, and I'm more concerned about portraying it in a roleplaying game anyway.)
Anyway, the servant who is quite competent (unlike early Alfred, but his modern incarnation), and who is doing it not because of some spell or mind-control or because he hopes to be gifted with eternal life, but rather because he owes the vampire, and worked for him before the change, and continues to work for him after.
That might work in the context of a mob family, too, where the capo becomes vampirized.
What an off-beat Icons scenario: Gang war, but one side is headed by Octofather and the other by the vampire capo. ...I might scribble some notes down on that...
