Youjuu Busou Buraiou

A clan of demons that have existed since the Asuka period and protects the emperor from evil beasts called "monsters". Until now, they have continued to secretly fight fierce battles with these monsters. The demons that resisted the monsters evolved by absorbing human knowledge, and some of the demons that acquired cunning created an organization called the Grudges and tried to take over the human world. A battle for the fate of two races, humans and beasts. What is going to happen?

(Source: Beaglee, translated)