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.
Yeah, I'd heard that.
.نعم، سمعتُ بذلك
Ja, das ist mir bekannt.
Sí, eso escuché.
Sí, eso escuché.
Oui, je le savais.
Sì, l'avevo sentito.
Ah, disso eu sabia.
Да, я слышал.