Nezu is a humanoid, mouse-headed animal who is the principal of U.A. and one of a few non-human animals to develop a Quirk. His Quirk is High Spec, which allows him to have anthropomorphic abilities and extreme intelligence. As befitting to his role as principal of an academy for heroes, Nezu is an eccentric, polite, and persistent educator. He is quite self-aware of his odd appearance and introduces himself by pointing it out. He can be very long-winded at times when explaining or educating. He is not above putting himself on the front lines or in danger, with his focus being the safety of his students.