Ruka (Yuma Nakayama) is a young vampire, but hasn't yet matured into a full-fledged vampire. His canines have yet to develop, which means he still hasn't tasted human blood. In order to get him prepared, he is cast down into the world of humans, where he boards with Jiro (Shiro Ito), the owner of a Chinese restaurant, and enrolls in high school. His homeroom teacher (Rosa Kato) is a cheerful, though meddlesome, young woman who catches the fledgling bloodsucker off-guard. Is he actually falling in love with a mortal?