Blood Lad

Plot
Blood Lad follows Staz, a vampire that is obsessed with the human world, and Fuyumi, a human girl that was killed and turned into a ghost after wandering into the Demon World. Staz promises to help Fuyumi regain her humanity by bringing her back to life, as it means that he would be able to visit the human world.

Official

 * Blood Lad Anime Website (Japanese)