Vampire Knight is a shojo manga and anime series written by Mr. Matsuri Hino. The story began of a child in a stormy winter, wherein she was attacked by a vampire yet save by another vampire. After 10 years, Yuuki cross was adopted by the headmaster of the Cross Academy, Kaien Cross. Cross Academy is divided by two; a group of ordinary humans and a group of vicious vampires led by Kaname Kuran a pureblood vampire. Yuuki along with his childhood friend, Zero are the school guardians(prefects) at Cross Academy. Their duty is to protect the human "Day Class" students from the vampire "Night Class" students and to ensure that the human students do not discover the secret of the Night Class (they are vampires).
Zero was bitten by a pureblood vampire when he was young. His family was killed from the rage of a pureblood vampire for killing his love one. If a human bitten by a pureblood vampire he will turn into a Level E vampire. Yuuki was worried for turning into a Level E, she offer herself feeding him so he won't be in outrage. Kaname, for the sake of Yuuki, he has the power to make zero not turning into a Level E. He let Zero drink Kaname's blood so he would turn into a true vampire.
