First off Dragon we could double to each play a dragon and each play a rider. They are paired by a council with no desicion of their own. They are being prepared for a war but must learn everything about the relationship between Dragon and Rider first. 

Avanhelsing would this be medieval? I like the plot. There could be some awesome twists in this. My girl could be a hunter of rogue supernatural beings. Modern would work for this as well.