Heiji Uzumasa Ookawa  

, 大川 平次 渦正

The Headmaster of Ninjutsu Academy is an eccentric individual who enjoys indulging in whatever sudden ideas come to mind. He has a reputation for being a genius ninja in his youth and often takes pride in being the center of attention, whether through handing out bromides or figures of himself as prizes during events. Despite this, he has gathered a vast network of both friends and enemies over the years and is often targeted by assassination plots. In the anime, he has a granddaughter named Shige who attends the kunoichi class and his constant companion is a ninja dog named Hemu Hemu.