Zero Kiryuu (錐生 零, Kiryūu Zero)

• who is a year older than Yuki Cross, comes from a vampire hunting lineage. His family was killed by the pureblood vampire Shizuka Hio because of one of the assignments his parents carried out. Zero was taken in by the headmaster of Cross Academy and became a Prefect (Guardian), alongside Yuki Cross. He has a great hatred for vampires because of what happened to his parents, but it is later revealed that he himself is a vampire as a result of Shizuka's attack. It is also later revealed that his twin brother, Ichiru, also survived the attack and lived at Shizuka's side. After he consumes Shizuka, Kaname lets Zero drink some of his blood to keep Zero from losing control of himself in order to protect Yuki.