Your lore is excellent Black Elk and your example shows the creepiness of Mizora lurking. Especially when, as fylimar pointed out, she isn't invited.
I feel like your Mizora is much more layered than the one I met and my party wouldn't willingly allow a stranger to be tormented let alone someone they know.
Mizora and Raphael as particular enemies for Wyll (or a Wyll and Karlach team-up) would be great. As everyone has said Wyll should have more story.
Speaking of which some clever players have figured out how to fullfill Wyll's contract and still recruit Karlach and once it's done have them both healthy and well. It may be a bit hard in both senses and slightly buggy at present but it's exactly the kind of loophole you want to cheat the devil. I wish it was a built-in scheme so Wyll and Karlach could have a good lauigh at Mizora.
So I love Mizora in this game!
But I'm pretty sure that's cause I really enjoyed the film "Bedazzled" lol. Like give me half a rotten tomato on that one and I could still get down! Or that show "Evil" which explores similar themes. I think it works for me, cause she's just another thing he has to overcome, and her taunts and torments make him super relatable. Like he's all hung up on that bad decision and on this ex, a literal devil on his shoulder - thwarting all his plans to make a clean break, complete with the disapproving parent dynamic even. Like there's just a lot there to mine hehe.
That said I think she should always be on the far side of whatever camp location, and not leering, like right next to his bed, 3 feet away.
It's super easy to imagine the shoe on the other foot here. For example, I know for a near certainty that if they flipped the script, the reception might be rather different. For example...
If the Origin character was named Wyllimina, and she was being hounded at camp by some unrelenting incubus named Mizoro, there'd probably be a dozen different options to fireball that dude into the next zip code lol. I mean right?
So there's that!
I do think she enhances Wyll's character by being so adversarial and litigious and omnipresent though. I also think her character would have been great as a whole separate thing for Warlock PCs, as opposed to just being attached to Wyll at the hip. It makes his late game romance path a bit awkward I'd guess, that you can't just tell her to kick rocks.
My first ever BG3 playthrough was as a Warlock and I got all excited thinking that Raphael and Mizora were there specifically for me, for my Tav, cause I chose that class, but then kinda sad when I realized it was a generic/origin companion specific type thing.
Still, Wyll is great! So I think she just can't let him go. In order to make it work in my head canon, I have to give her a secret motivation where she actually somehow knows that Wyll will make the right choices and in the end that she also wants that for him. Again, pretty similar to Bedazzled, the B flick take. For all her snark and supposed self interest, she does protect Ravengard at that one point, even though it's totally her fault that he was even there to begin with! Lol
I wouldn't expect her to ever admit contrition, but I kinda get that from her anyway. And Devils sort of exist outside of normal space-time, so maybe it works somehow where she's actually a better angel than we give her credit for, sorta nudging him along towards his destiny, like a lot of the devilish looking peeps in this game who subvert like that. I feel like if I was at comic con I'd totally want her to sign the poster too heheh.
Despite all that though, I do think the PC should be able to tell Mizora to take a hike, and then talk some serious shit on her with Karlach once Mizora is out of earshot. That'd be a nice touch!
