Demi-chan wa Kataritai Temporada 1 Episódio 1

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, hes never even met one. But then the school gains a new math teacher, Satou Sakie... who happens to be a succubus.