I know it's your comic, and you have the final say in all of this stuff, but if I were to do it, I'd make it so that the parent vampires are all like conservative and mainstream and not-gothy, and have the kid be like a goth or part of some other counter culture. He'd hang out with other goth kids who are all like 'were vampires' but aren't, and he'd be totally into gothy stuff, but would drink stuff like coke and beer/wine, instead of the perfectly legal blood that you get at the super market. (That would be a hilarious image in and of itself, like those little bags of blood from hospitals and cans of bloody soda.)
Something you really ought to consider is how common vampires are in the world you're talking about. Are they like common, and everyone knows about them, or does he have to hide his identity and not smile or everyone will find him out? Do vampires know other vampires? Like, would it be something like, "You know the thompsons down the street? They're vampires." Can he go out into the sun? Is he afraid/allergic to garlic?
You should totally do it, though. It seems like an awesome idea and I'd definately read it.
