Gundham has an eccentric and somewhat dark personality, his delusions of self-grandeur likely stemming from an inferiority complex and chuunibyou syndrome. He claims that he was gifted with evil powers of the underworld, the result of "an angel and a devil" joining together. In terms of combat, Gundham is surprisingly so powerful that he took on an army of heavily armed reserve course students with Nekomaru's assistance and fight Nekomaru in a one-on-one fight.