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.
Oh! By the way, I found a really 
funny video yesterday!
!صحيح! عثرتُ على شريط مضحك للغاية البارحة
¡Cierto! ¡Encontré un video
divertido ayer!
¡Es verdad! ¡Ayer encontré
un vídeo muy gracioso!
Au fait, j’ai trouvé
un truc marrant, hier.
A proposito!
Ieri ho trovato un video buffissimo!
Ah, sim! Achei esse 
vídeo bacana ontem!
А, кстати, я вчера нашла
такое интересное видео!