Glecia Snape Prince Slytherin was the name Severus and Lord Voldemort finally settled on, drawn from the Seventy-Two Demons of Goetia.
Glecia's name was taken from the twenty-fifth demon on the pillar, Glasya-Labolas.
He was the twenty-fifth spirit of the seventy-two demons of King Solomon, depicted as a winged dog with the wings of a griffin.
Chapter 63