From swe3t+moans BLScanslation:

"This place is a den for those who are not human.”
Yuki Shuri, a high school teacher forced to resign from the school where he was working because of a certain incident, is assigned to a new post at Karasudai private school. On the first day in the new school, he tried to save a bird from a dog’s mouth but the dog transformed into a demon instead. What else is going to happen in this school for wild students who are “not human."

A lonely demon and a high school teacher. Two miserable people, one because of a deep scar, and the other from the darkness in his heart. Hanami Hana sensei draws out a mysterious • love story!