A few years ago, I began working on a piece that involved a vampire and a werewolf. Since then, I've read any number of books that involved either a vampire/werewolf team or a main character of one persuasion, with an occasional appearance by the other. These days, I'm not only working with one such team, I now have another, set on another 'Earth universe'. And for that matter, I also have two other universes that include vampires and werewolves, though not necessarily as main characters.
In the instance of using a type of character that is as well known as vampires, which has been used, re-thought, and sometimes re-invented by any number of other writers, one must be careful to create something a little different in 'your' vampires. I am not that familiar with the original Dracula – even that story has been retold and re-imagined a number of times – and have no idea how Dracula became a vampire, although I do remember how he turned humans into subservient vampires. If that was the only way of creating a vampire, there would not have been a Dracula. So, how does one start a race of vampires? Even if you don't explicitly explain it in your story, you should have some idea how it happened.
Are there a lot of vampires in your universe, or only a few? Several recent writers have a huge population of vampires 'coming out' and mingling with humans. They seem to make it work, but to my mind, such a large number of vampires would run the risk of turning humans into nothing more than a food source. Therefore, I tend to make my vampires extremely rare. Mine also do not burst into flames in sunlight, but they do 'burn at the drop of a sunbeam', so they tend to sleep during the day. And they can survive for a very long time on 'extremely rare' pieces of meat, although if you get them mad, they might drain your blood to teach you a lesson. If they live a long time, how do they manage to avoid being detected, or do they even try?
All characters take thought about their background, their lives. When you're using a type of character that someone else has already created, you must either follow the 'rules' about that type of character, or create your own rules. Whichever way you go, have a reason for that decision.
Next weekend is another convention. Don't be surprised if I'm late … again. Trudy