En Zu calls himself the storm genie and the king of darkness. His true form is an indu gud, a huge eagle with the head of a lion. During his first encounter with Pam, he had for some reason become a huge, malformed beast which was being hunted and fought by Linfa. Pam's heirloom necklace knocked En Zu out and shrunk him dramatically, allowing Pam to claim him as her familiar. En Zu does not relish the relationship, as he views Pam as a weakling and a fool, although he does look out for her as a familiar should. Alas, Pam has become convinced that En Zu, whom she addresses as "Zu-kun", is a pervert; in his combat form, which looks like a young male devil, Zu has managed to shock Pam's sensibilities without meaning to. Additionally, En Zu seems to have lost a lot of his memory from before the time when he was claimed as Pam's familiar, due to psychological trauma he suffered before Pam took him. Recent information indicates that En Zu is a usurper and that he had been imprisoned for a long time before being released by Remi and went on his ill-fated rampage. (Wiki)