Blood+

Saya Otonashi is a normal girl living with her adopted family in Okinawa City. She has anemia and can't remember anything from before last year. One night, something bad happens to her at school. A man called Haji saves her. He makes her drink his blood and then she is able to fight off a scary monster. Saya then finds out about a group called Red Shield that is fighting monsters. She and Haji must help them to defeat the monsters and figure out Saya's past.