Izumi is Mikan's father and the former moderating teacher of Special Ability Class. His ability was discovered when he was already an adult. He entered the Academy as a teacher when he was 22, nineteen years prior to the year the main story is taking place in. His cause of death is not known (it was said to be suicide, but the truth is found it in Chapter 116; he was accidentally killed by Persona under the orders of the Elementary School Principal), but Yuka believed that he was murdered by someone working in the Academy. The High School Principal is in fact Izumi's older brother and also the one who accidentally discovered Izumi's Alice through seeing a photo of him in one of their letter correspondences using his own ability to detect other people's Alice by seeing them in person or in photographs. In contrast to his older brother's more serious character, Izumi has a very cheerful and outgoing personality, which was inherited by Mikan, and was often he was scolded by Jinno-sensei. He was very popular with the students. However, when provoked, he can be very intimidating. He was the former leader of a motorcycle gang back in his hometown. Two years after his arrival, Izumi is informed by Jinno that he is going to be put in charge of the new Special Ability Class, as well as the new 'special' students within the class. Later on, he was summoned by the Elementary School Principal. The principal informed him that the new 'special' students he is receiving have dangerous abilities. Izumi never thought he would be asked to supervise and severely punish the special students. Being the teacher with the Nullification Alice, it was a job specifically for him. Izumi was not happy at all by this and opposed it greatly. He is also a pervert at times. For example he wondered if he would be teaching high school girls, and also proclaimed to Yuka "that he could see her panties clearly" when they first met and Yuka was trying to escape out of the Academy.