A Dragon's Vampire Mate

Jason is a dragon-human hybrid. His mate, however, is a vampire. Jason's mate went missing a few months into their first year of Hogwarts. Jason suspects that Dumbledore has something to do with her disappearance. An angry dragon is something not to mess with, but a very hungry and angry vampire, it's best not to get in its way.

Harry Potter. The boy who lived, the chosen one, golden boy, and many other names. Comes into a shocking inheritance. What does Voldemort have to with it? Why is Snape being less meaner then usual? And what is up with Ron and Hermione disappearing all the time?