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.
Ah, you're here.
.لقد وصلتِ
Ah, da sind Sie ja.
Ah, aquí está.
Ah, aquí está.
Oh, finalmente è arrivata.
Ah, chegou, então?
О, наконец-то.