Shirogane (シロガネ), also known as Ieiri (イエイリ), is a professor and a former teacher at Sudou Kaname's school.
Shirogane has neatly combed back black hair. He wears a white collared shirt, a vest, a suit coat with patterns, a striped necktie, and dress pants with the same pattern as his coat.
Shirogane is shown to obsessed with evolution and sigils, stating that he is in pursuit of the possibilities of sigils, which he refers to as the possibilities of humanity. Because of this, he once expressed the desire to travel to World Line O since they were more knowledgeable about sigils than his own world. He has no problem with having students kill each other, as shown when he had Tabata Shigeo and Oosako fight to the death to see which would be the better product. He doesn't seem to have an interest in other people, telling Gyokuto Sakuji that he didn't care about Kaname or the American army, though he will still acknowledge people, telling the Game Master that Kaname's become the alpha of their world just as Oboro claimed.