Vampire Knight

is a shōjo manga and anime series written by Matsuri Hino. The series premiered in the January 2005 issue of LaLa magazine and is still on-going. Chapters are collected and published in tankōbon by Hakusensha, with eleven volumes currently released in Japan. The manga series is licensed in English by Viz Media, who has released ten volumes so far. The English adaptation premiered in the July 2006 issue of Viz's Shojo Beat magazine, with the collected volumes being published on a quarterly basis.

Two drama CDs were created for the series, as well as a twenty-six episode anime adaptation. Produced by Studio Deen, the anime series' first season aired in Japan on TV Tokyo between April 8, 2008 and July 1, 2008. The second season, titled Vampire Knight Guilty aired on the same station from October 7, 2008 and December 30, 2008. The anime uses many of the same voice actors as were used for the drama CDs. The anime adaptations have been licensed for release in North America by Viz Media, the DVD will be released on July 20, 2010.

Plot
Yuki Cross' earliest memory is of being all alone on a snowy night in winter, when she was attacked by an evil "Level E" vampire and saved by a powerful but kind vampire named Kaname Kuran. Ten years later, Yuki, along with her childhood friend, Zero Kiryu are school guardians at the prestigious Cross Academy where her adopted father is the headmaster. The school is hosting an experimental program that is trying to prove that humans and vampires can live together peacefully, in a quest for coexistence.

The job of the guardians is to make sure that peace is maintained and to protect the human "Day Class" students from the vampire "Night Class" students if necessary. They also make sure that the human students do not discover that the Night Class members are all actually vampires. They go by the guise as "prefects" or "disciplinary committee members" so as to not blow their secret. The day class students try to follow the night class students around, as they are all very beautiful, intelligent, and often flirts.

The night class is made up of high-class vampires (Levels A and B), as there is a hierarchy among vampire society. Level A includes only pure bloods, the rarest, most elite, and most powerful class, whose bloodlines have never mixed with humans. Pure bloods are also the only kind of vampires who can bite a human and turn them into another vampire, and a pure blood's blood gives whoever drinks it greater powers. Level B are known as "Nobles" or "Aristocrats." These are also very powerful vampires, but not as much so as pure bloods. They also have a small amount of human blood in their ancestry. Levels C,D, and E include humans who have been turned by a pure blood rather than born as a vampire. These ex-humans will eventually go mad with blood lust and become a "Level E" if they are not stabilized by drinking the blood of the one who originally bit them in the first place. Stabilized ex-humans are known as "Level C" or "regular vampires", and humans who have been bitten but have not gone mad are "Level D".

The story follows Yuki's discovery that Zero had been turned into a vampire and her struggle to keep him sane, since he had not been stabilized, and prevent his condition from deteriorating into the lowest form of vampire, the monstrous Level E. Zero's parents were vampire hunters, killed by a pure blood out for revenge, and who also bit him in the process and took his twin brother, assumed to be dead. He hates what he has become, and fears that he will succumb to blood lust and murder everyone. He feels that the only option is to kill himself, which Yuki tries to help him avoid. Meanwhile, she also tries to deal with her seemingly unobtainable love for her hero, Kaname, who also happens to be a pure blood- the only one in the night class.