Mikami is characterized as having a strong sense of justice that has developed over the course of his childhood. He detests crime and, similar to Light, expresses a fervent passion for punishing evil. His sense of justice, however, has developed into a rather "black and white" understanding of people, and he goes as far as to label everyone he meets as either good or evil. Mikami is also notable for adhering to a strict, daily schedule, a trait noticed by both Light and Near. For instance, he exercises at a gym at the same time on the same days each week, regardless of holidays, and he has been a member of this gym for years. Whenever he judges criminals in his Death Note, names are written down in straight columns on every page. He also fills up exactly one page with names each day - a feat which Light notes as "obsessive."Mikami appears to struggle with a form of mental instability, though it is unclear if he was born that way, if it was a product of his traumatic environment, or both. For instance, Mikami repeatedly recites "delete" (削除, sakujo) whenever he writes a name in his notebook.