In Love With a vampire

When his parents are killed in a store holdup, Rio is taken in by a couple living in the land of ooo. He struggles with the outside world and rarely speaks. He is locked away in his room listening to music and reading horror stories, he has no other friends beside the shadows on his wall. One day, when Rio meets a mysterious girl he thinks nothing of it, Until she takes him to her lair. She seems normal but that's when she let's him in on a dark secret.