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.
A demi-human whose head is 
separate from its body?
تقصدين أنصاف البشر الّذين لديهم
رؤوس منفصلة عن أجسادهم؟
Ein Halbdämon, dessen Kopf
vom Körper getrennt ist.
¿Un semihumano con la cabeza
separada del cuerpo?
¿Un semihumano con la cabeza
separada del cuerpo?
Une ajin dont le corps
et la tête sont séparés ?
Un semiumano la cui testa è separata dal corpo?
Uma meio-humana cuja 
cabeça foi separada do corpo?
Полулюдей, у которых
голова отделена от тела?