Xazal

Xazal is a High Demon in the form of a male with black hair. Xazal's eyes are colored yellow from the usual red due to the manner of his High Demon transformation. Instead of ingesting the Demon King's blood as a Low Demon, he consumed many Low Demons and evolved.

Creation
Xazal was the first Demon to evolve into a High Demon via the consumption of other Low Demons, therefore making him eligible to become an Arch-Demon.