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.
See? There's the bell.
.أرأيت؟ هذا هو الجرس
Hörst du? Das war die Glocke!
Ab ins Klassenzimmer!
¿Ves? La campana.
¿Ves? El timbre.
Sentito? È suonata la campanella.
Ouviu? É o sinal.
Слышишь? Звонок.