After Sulyvahn took out the Royal family from Irithyll and declared himself as the Pontiff by using his dark magic and the Deacons, he needed a Lord of Cinder to link the fire. Aldritch, the Devourer of Gods may or may not willingly was chosen to be the Cinder Lord as an ally of Sulyvahn. As his title grants him the power of gods, he appears as Gwyndolin the Dark Sun of Lord Gwyn, leader of the Blade of the Dark Moon covenant. Aldrich possessed his look as well as his abilities. After Aldritch devoured him slowly in his dream while Gwyndolin was ill, the protection of Anor Londo, the city of Gods was fell and became a dark and cold desolation.
This depiction of Aldrich inspired by the artist Francisco Goya’s “Saturn devouring his son” painting.