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.
You're always pushing your luck, Onee-chan!
!تتوقّعين دائمًا الإفلات بهذا يا أختي
Schieb dir dein
Schwesterchen sonst wohin!
¡Para ser mi hermana,
abusas de tu suerte!
¡Para ser mi hermana,
abusas de tu suerte!
T’as de la chance de m’avoir !
Tiri troppo la corda, sorellona...
Você sempre abusando da sorte, mana!
Не испытывай моё терпение, сестрица!