Vampire Knight is an amazing manga series! It's about this girl Yuuki who is saved from a rogue vampire by a kind vampire, Kaname Kuran. She is 5 at the time and can't remember anything before that time. She is raised by the headmaster of a school where vampires and humans coexist, except for the fact that the day class doesnt know that night class are vampires.... She is confused and stressed about her past alot later in the series... but you'll be totally taken aback when her past is revealed, i guarantee it ;)
( that is unless someone spoils it for you, i hate spoilers...)
The anime gets cut kinda short, but still has a good ending i suppose... the manga is still ongoing and goes into alot more depth that the anime series... i suggest watching the anime first, and then reading the manga.