Demon King

The Demon King is Glenda's father, and the ruler of the Demon World.

Personality
A typical father, he wanted Glenda to be happy, despite her hating him for his personality. Obsessed with her daughter's development, he archived everything Glenda does and archived it, to the point of filling a room with her activities alone.

He also a personality that annoys his wife and daughter, to the point of his wife leaving him.

Appearance
A typical Demon feature, with horns sprouting on his head. He has long ears with earrings on both.

Background
The King of the Demon World, he ruled the land with an iron fisted façade, in reality, his subjects loved him for that.

Glenda
His daughter. A typical father to his daughter, he pampers and spoils Glenda, to the latter's annoyance. He also was obsessed with his daughter's development.

Glenda's Mother
His relationship with his wife was strained, to the point Glenda scolded him with their conflicts.

Cube
He was not aware that Cube was exiled from the Demon World, even allowing the demon exile to massage him.

Trivia

 * He is quite the ironic representation of the Devil, having a soft heart for his subjects and his daughter.
 * His proper name is never revealed in the anime series.