I like to read lots of different series because I like that every one has a different spin on vampires.
I like the mystery, each vampire has their own mystery to solve in their world that they don't want to expose to the one they love.
I guess it's because they're supposedly live forever and never age, but also a lot of twists and turns as each story is unique and they live through different times and epochs which is quite fascinating I think. Plus, living so long, they don't really have to worry about trivial things like buying the house, car, paying for food and travel, etc.
They remind me of me.
First Vampire book was Blue Bloods and I have no idea how i got so hooked