To prepare for the upcoming exam, Zero tutors Yuki, but all the while, she notices something wrong with him. Meanwhile, at the Moon Dormitory, Kaname confronts Maria in his room...

Maria's masked servant is none other than Zero's twin brother, Ichiru, whom Zero has not seen since their separation long ago...

Yuki learns that Maria's true identity is Shizuka, the pureblood vampire who bit Zero and turned him into a vampire. With this information, Yuki accepts a deal from Shizuka and offers her blood in order to save Zero...