When Kanzaki gets a letter from Mari Setogaya asking to satisfy of their school`s PE garage room in the course of the lunch break, he believes he could be receiving a love confession. He turns up eagerly, handiest to be attacked via way of means of his intended admirer. The lovely female attempts to knock him unconscious, however whilst she fails miserably, she explains that she is a vampire and had desired to feed on him. Feeling pity for her hopeless state, Kanzaki reluctantly yields and permits her to drink his blood. As it turns out, Mari can not stand the flavor of uncooked blood however will perish with out the vitamins it contains. Kanzaki is brief to discover a solution, imparting her a distinct physical fluid to consume—and Setogaya right away falls head over heels with this new flavor. The quickly begin assembly regularly, and as time is going via way of means of, their courting evolves into some thing greater than simply casual "meals" spent together.