The blood protection inside of Harry blocked His killing curse and burned His host body to ashes, yet failed to stop His soul from entering his body? Oh wait, it didn't! Harry's blood protection fights against Voldemort's soul and something new is created...a new soul and companion. Harry thinks it is unfair that she doesn't have a body of her own...well he is going to change that!
EnniNova:
-А Снейп-то, говорят, не настоящий!
- А какой?
- Так черный же!
- Это в каком смысле, черный?
- Во всех!
- Правда? Это точно?
- Ну, так автор говорит. И вообще, истина как всегда, где-то рядом.