Yakan Hikou: Vampire Knight

Hana Usagi is a first-year high school girl. She lives with her stepbrother, Yui, in a house known as "The Mansion of Tragedy." She thinks of herself as just an ordinary schoolgirl.... but every night, she takes a "secret walk" looking to avenge her parents' murder. Meanwhile, her stepbrother keeps begging for a taste of her "blood." Is it scary... to have your blood sucked? Or... does it feel good? Humans and vampires, love and mystery intertwine, in a bloodsucking dark fantasy! (Source: Shogakukan, translated)