Blood+

From Dark Horse:

Suffering from extreme amnesia, high school student Saya Otonoshi can't remember anything from her life beyond the last year. Living with a foster family outside a military base in Okinawa, Japan, Saya's attempts to live a normal life are shattered when a Chiropteran, a horrific vampire-like monster, attacks her. Saved at the last minute by a mysterious man named Hagi, Saya is presented with a sword that awakens in her a warrior's skills and bloodlust, and sets her on a course that will lead her to the answers of her missing memories, and into battle against a race of creatures intent on destroying the world.

The epic adventure that began in the groundbreaking film Blood: the Last Vampire and has continued through the worldwide phenomenon TV series Blood+ is brought to life in this all-new series of novels adapting the hit show. Saya's journey of horror, magic, romance and mystery will stretch across time and around the world, expanding on the television series with new characters, new adventures and breathtaking action.