Cross Academy is an elite boarding school with two separate, isolated classes: the Day Class and the Night Class. On the surface, Yuuki Cross and Zero Kiryuu are prefects of the academy, and attempt to keep order between the students as classes rotate in the evenings. As the Night Class is full of utterly gorgeous elites, this can sometimes prove to be a bit difficult. It is completely necessary, however, as those "elites" are actually vampires. Yuuki and Zero act as guardians, protecting the secrets of the Night Class and the safety of their ignorant morning counterparts.