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.
Um... My train was delayed due 
to a car inspection, and...
عفوًا... تأخّر قطاري بسبب تفتيش 
...في المقطورات و
Ähm …
Eh, el tren se retrasó
por una inspección del vagón, y…
Bueno, el tren se retrasó
por una inspección del vagón, y…
Mon train est resté à l’arrêt
un bon moment.
Ecco... il mio treno ha fatto ritardo
per via di un controllo a una vettura...
Bem, o meu trem se atrasou por 
causa de uma inspeção no vagão, aí...
Э... Электричку задержали
из-за инспекции...