Thank-you, Thank-you, Citrine Witch, for posting the tenets of The Black Veil in response to this question.
Yes, this is a REAL set of ethical and etiquette rules for real vampires. If you don't believe it, Google "Black Veil". It was even mentioned in an episode of CSI. There are several slightly different versions that you might come across online. It's been revised a few times, and different groups may adopt slightly different versions. According to Michelle Belanger, it was originally modeled after the laws of vampire behavior in the game "Vampire: the Masquerade", but has since been made less dramatic in its prose and more practical. As you can see, there are no punishments included for not following these rules. They are thus suggestions for proper behavior, rather than laws.
I'm reserving my judgment on whether Elmo is a real vampire or not. It's possible she could be a vampire and not know about The Black Veil. It's also rare, but possible for vampires to have naturally longer canines (just as any human can). I know one hereditary sang who says he had longer canines naturally, but his father had them filed down when he was a kid.