Idea No.1:
Time Period- It could be literally anything...like we could do Wild West if you want
Basically it's just your same old Hunter and creature scenario, so person A is hunting person B (who would be a vampire).

Idea No.2:
Time Period- Any
It's a stormy night and person A gets lost in it. They wander around until they find a big, sorta creepy mansion, though it's out of the pouring rain and cold, so they go inside. This is only to somehow find out that there is a vampire coven that lives there, and person B finds them first.

I may add some ideas here, but I can't think right now. If you've got any ideas, let me know and we can develop them and rp them!