(this is an opinion, don't come after me) I don't know. She's just so bitchy for absolutely no reason. Sure, in episode 3, that was justified, but in other episodes she's rude and grouchy for no reason, she's terrible at her job, rude to moxxie for no reason (even if it's for comedic purposes) and like moxxie said, acts like some troubled teenager. (She's 22, a full grown adult.) Now, I can see why she gets mad at blitzø only SOMETIMES, and other than that Millie has more character then her. All the fans she has are kinda concerning, as she barley has any character to her besides being blitzø's adopted daughter, and being some emo hellhound. Now, it's probably cause of bad experiences in the past for her, but I just can't see myself sympathizing for her as of now.