Anime watcher here only, so please no spoilers!
After watching episode 5 and the ending... my suspicions weren't drawn to Qifrey, but rather the Witch Society as a whole, and the brimmed-hats role in it.
Here's what I understand so far. Some odd years ago, a few head witches decided to wipe the entirety of humanity's mind from the use of magic, only trusting a select few individuals within their inner circle to use magic. From there, they kept the secret of magic from everyone, made rules, and would wipe the minds of anyone who would discover the truth about magic.
... which is EXTREMELY screwed up, if you think about it.
It reminds me of something akin to State Censorship and false histories...
Here's what's got me suspicious about the entire Witch society as a whole:
The mind-erasure spell. The only spell allowed to be used on by humans. From what it is said by Qifrey, it's a spell only to be used to make civilians who discover the truth of casting magic forget. But... that got me thinking. It's mind erasure. With no clear way of recovering these memories, who knows what else people are forgetting, or worse, what the witches are forgetting. The state says that it's only for that purpose, but it isn't like it can be ONLY used for that purpose.
How fast news spreads. When Coco first casted the forbidden magic spell and petrified her home, Qifrey was the only witch present within that area. The next morning, somehow news travelled so fast that by the time Coco landed at the Atelier, EVERYONE, including apprentices, knew. How could the general Witch society have known so quickly? Sure there's magic that can likely send information over vast differences, but over the course of one night? Seems like someone is leaking information to them...
The insistence of forming large Witch ateliers. When Qifrey visited the underwater city, a semi-important witch (I think?) insisted that he move down here, where he can easily get supplies and be amongst other Witches. But that seemed a little odd for me, as Qifrey was doing quite fine on his own, and he can always return to that spot whenever it strikes his fancy. And yet, they really suggest to keep him and his apprentices there as well. But why? I suspect that they want to keep an easier tab on everyone, and its ridiculously easy to do so when everyone is in a place you can predict and monitor using your own form of magic or information network.
The banning of forbidden magic and magic on humans. While it is said that this magic was used to hurt people... I have my suspicions. One notable thing was that Qifrey noted off-handedly that witches were not allowed to heal others or reverse the aging. But yet, that made no sense. It wasn't like people would figure out how magic works through that sort of thing, but they emphasize on preventing witches from ever doing that either themselves or others.
The hoarding of knowledge. Every spellbook ever written apparently has a copy show up directly at a library. This library is closed off too many and all people, causing only a select few to have access to their contents. The only people who reside in the library are the librarians, who very well may be people who assisted in the mass-delusion of magic. It seems odd that they have access to all these magical tomes, and yet, they would refuse and outright control how magic should be used.
The old story. It said that these were a bunch of "good witches who would never do harm," but what kind of good witch would have a ready-made spell that can physically make people forget an entire central part of their world? And have it in such a degree that it can span across the ENTIRETY of the world, leaving only a select few of THEIR choosing to enter into the world of Witches and magic? Was it really to 'prevent people from fighting?' Because if that was the case, there are ways of doing just that without having to remove a central part of the world.
The role of the Brimmed Hats. I found it odd that they mentioned that they were reminiscent of old witches, before the mass delusion. And that the brimmed hat we see refers to Coco as their savior, and that they are willing to hand out information freely. Is their plan just to cause mass chaos... or is it to perhaps, break the old order which restricts, censors, and outright can de-person someone and their knowledge without them ever knowing?
What do you guys think? (Sorry for the long post.)