Takahashi Tetsuo, a biology teacher at Shizaki High School, has been fascinated with "demi-humans," beings with characteristics that differ just slightly from humans, since he was in college. He wishes he could have a chance to talk with one, but since the demi-human population is fairly low, he's never even met one. But then the school gains a new math teacher, Satou Sakie... who happens to be a succubus.
Aren't demi-humans unusual to you?
أليس أنصاف البشر غير عاديّين في نظرك؟
¿Los semihumanos no te parecen raros?
¿Los semihumanos no te parecen raros?
Tu en vois souvent, des ajin ?
Non ti sembrano strani i semiumani?
Meio-humanos não são
 incomuns para você?
Разве полулюди для тебя не редкость?