I think it will take place in mystic falls unless everyone votes otherwise just because its a more familiar place.
You dont have to be one of the canon characters but we just have to make sure we fill most of the important roles, some people can even choose not to have an original character.
And i'll most likely base it off the shows so really all you need to know for this is just the character personalities(if you are playing one of the characters) and the rough lay out of the town :) and of course the rough storyline of the show. Like vervain, silver, the vampire hunters. Just stuff like that, which I'm also sure can be quickly found online lol