Manga Black Haze

Black Haze is the guy who takes the key, Ruda Krishi - he is a really well-known Black magician [Strike], one of the youngest but most powerful wizards on the planet. Despite this, recently his organization has just given him the opportunity to perform small tasks, such as organizing small payback schemes for customers and fulfilling orders.
One day, Rood meets the strong Duchess Dainer Artian, who asked for his firm help. Lidusis, her second boy, did not go to college very well, so she would like Rood to help him. To achieve this, Ruda should hide as a student of the famous school of Helios to find out why everyone else calls the duke's son "Monster." Naturally, Rood soon realizes that much more is happening in this unique college than it seems at first glance...