Yes, I do obsess over characters, that character always tends to be relevant in some why to my subject obsessions.
Ages ago I used to have an obsession with music stereotypes, emo being my most obsessed over. And I used to watch Hollyoaks just because of the character "Newt" because he was an emo and I only enjoyed Hollyoaks when he was in an episode, sometimes I watched the same one on youtube.
So now some characters in cartoons and stuff I get fixated on watching because they're relevant to my interests, for example I watch "The penguins of madagascar" and like that cartoon anyway, but all my favourite episodes have Mason and Phil in them.

Yeah at current my obsession really is super powers and I have been watching a single character from a show who has an ability that I think is like super neat. So I must know everything and watch everything this character does, because he will help me learn super powers. <---please do not ask my brain to explain its processes, it just is the way it is. Which is slow, dumb, and a bit awkward in firing up its neuron thrusters...lol