Diego Ijeiska

Diego Ijeiska is the headmaster of the Hero Academy Arclanisca and teacher of its elite selective class Jerga-Kanon in the anime adaptation of The Misfit of Demon King Academy. He is a source clone created by Eleonore Bianca, designed for educational purposes with strong compatibility to the holy magic Aske.

In appearance, Diego is depicted as a middle-aged man with messy brown hair tied in a ponytail, notable bags under his eyes, wearing a brown coat and white pants.

Personality-wise, he is arrogant, conceited, and deeply prejudiced against demons, viewing them as inferior and seeking their extermination. He falsely claims to be the reincarnation of the legendary Hero Kanon (as Diego Kanon Ijeiska) and orchestrates schemes to provoke conflict between humans and demons.

In the story (Season 1 episodes 9-13), Diego invites the Demon King Academy to an inter-academy exchange as a pretext for war preparations. He rigs events like a knowledge contest on holy magic to mock demons, cheats in an underwater exam by contaminating it with holy water (causing harm to demons), and ambushes Misha Necron in a hidden temple, stabbing her repeatedly out of malice. Anos Voldigoad intervenes, kills Diego, revives him for interrogation, and transforms him into a demonic monster reflecting his ugly, spiteful heart using a curse. Diego later leads a demon-subjugation army but is ultimately defeated and killed for good by Anos. He wields an Enhance Sword and uses holy magic, but his power is no match for Anos.