Aggril was an old grey hedgehog who brewed many types of cordial, and was, by nature, very moody and temperamental. Aggril lived in a hollow oak north of Noonvale by a cherry grove that he protected fiercely, believing he had sole custody of the fruits it offered and there was no persuading him otherwise. He wore square spectacles and used a blackthorn walking stick.
By the command of Boldred the Skyqueen, he told Martin the Warrior, Rose, Grumm, and Pallum the directions to Rose's residence in Noonvale. However, he did not trust his guests, and gave them a potent sleeping agent before sending them in the care of Boldred and the otters. It was alleged that, had it not been for Boldred's presence, he might have administered a lethal dose.