Why is there no 'horror' tag? What. On that note, I like to write horror and as a vampire roleplay, expect there to [i]be[/i] horror and blood and gore and all that fun stuff. Not talking Twilight vampires here.
Otherwise, jumping right in.

The premise is pretty simple. Vampires exist and there is a 'taskforce' of hunters called regulators that keep them in check, more or less. Vampires have a sort of government among themselves and their own set of laws to avoid crossing the regulators. They're supposed to only feed on the dregs of society; criminals and the sort. There are a few "civilians" who, in some fashion or another during their lives, became aware of the existence of vampires and make cash by selling blood too. Turning people is generally frowned upon and is something that is regulated as well, to avoid overpopulation for an "immortal" race (duh). Some vampire starts making a den of vampires left and right, willy-nilly, chances are they're gonna have a regulator showing up to clean house.
I kind of like the idea of having all sorts of different vampires, as well. Almost every culture seems to have its own myths and legends of "vampires" and this would supply a lot of diversity for different "breeds" all over the world. Always something new to throw around.

The regulators are a relatively small group. It's an inherited, family business and for the [i]most[/i] part, if someone's a regulator, their family has been doing it for centuries. It's in the blood. There are cases of people falling into the work, though. Probably not more than a couple thousand regulators throughout the world and their organization are pretty loose as far as orders go. They catch wind of rogue vampires, go and take care of it. 

I have a starting point for a plot that involves a rogue group of vampires who have started dealing with human trafficking, mostly outsourced from other countries, to fund feeding, and it's just going to sort of snowball from there into more and more 'wtf shit is this'. How and where it develops would kind of depend on what character(s) you, as my partner, whip up. 

My only stipulations for this RP is that I would really appreciate someone who can handle multiple characters. They don't have to be main characters or anything, you can still have 'one' main character if you want, but I've already got three or four 'main' characters in mind to play and there can/will possibly be a lot of different angles to this. Other than that, just drive the RP with me. Got an idea, let's do it. Don't leave me to run the plot all on my lonesome. The only other thing is that I don't do character sheets. If you have or do them that's fine, but it's not something I do. 

Otherwise, go crazy. PM me or whatever. I'm open to discussion and adjustments and suggestions.
RP will be over PMs.