Fiducius was the dean of Cheiron's Academy and the tuition collector. He is extremely uptight and fussy with students misbehaving, but it is revealed that this is because he wants to push them to be their best and not end up like his son, Pythias Fiducius, who was once a student until he fell in with criminals and left ("Teacher's Pests").
When Cheiron went on vacation during Prank Days, Fiducius was left in charge of the Academy. Initially, he banned all pranks, but after Hercules thwarted an attempt on Jason's life by Buterus, Fiducius reinstated Prank Days (YH "Get Jason").
