Mikage is the pink-haired head of the popular Mikage Seminar at Ohtori Academy. Originally he was Nemuro, a professor at Ohtori Academy working a project to "obtain eternity". Emotionless and uncaring, he learned to feel when he fell in love with Tokiko, and threw himself into his research in order to save her ailing brother Mamiya and preserve their family forever. His dreams were dashed when Akio seduced Tokiko and Mamiya died, causing him to burn down the dormitory because he believed it to be the last step to opening the gate to "revolutionize the world", killing the 100 boys inside its walls.
Source from Wikipeida