#...also the vampires are a Problem because they're major factors in both series

[incomingalbatross]

Could the City Between and the Dresden Files conceivably share a universe? How would Harry Dresden fare in the City Between?

oh HMMMM

They might be able to! The main conceit of City Between, worldbuilding-wise, is basically that the Fantasy Dimension is occupying the same space as the Human Dimension as a default thing - Fantasy Dimension is Behind - and Between is the soft space in the middle that things and people can go through. This does not exactly exist in Dresden Files, but I feel like it could validly coexist with its worldbuilding.

On the other side of things, the fae and other Behindkind seem to live in a more limited world than the Dresden Files? They're very firm that humans don't have magic (though whether they're right is another question), there seems to only be one kind of werewolf, etc. However, this could easily mean that the Behindkind just don't interact enough with the human world to be aware of all the forces in it.

Politically it's a little trickier - the ruling class of Behindkind are fae, which ought to have some relationship with the Winter or Summer Courts of Dresdenverse. However, they have their own ruler, the King Behind, who is a sort of Fisher King-figure to the whole world/dimension of Behind. (I don't think his authority practically extends over everyone in his territory, but certainly there are no other sovereign powers in opposition to him.)

I think if you explained Behind as its own particular dimension of what Harry would call the Nevernever, and glossed over some details on both sides, you could make it work. The main points are A) putting it outside of Mab and Titania's jurisdiction, B) explaining why these fae don't have apparent history with the White Council, and C) minor details like "do these lycanthropes/vampires/etc. match any of the Dresdenverse ones" and "why do the Behindkind have Seelie and Unseelie lords that aren't in the Dresdenverse Courts."

(I do default to explaining other canons within the framework of the Dresden canon, simply because there's so much of the Dresden canon and it seems designed to keep fitting new elements.)

As for how Harry would do there?

Well. First point to make is that the titular City Between is Hobart, Australia. I do not think Harry would enjoy being in Australia. :P

Strengthwise, it depends where he is in his own series, but I think Harry would be a match for most of the CB players in combat. Taking fae and such by surprise is kind of his thing, and they're culturally arrogant enough that I don't think they would be prepared for either a human spellslinger or a gun. They're good at carnage! But he's very good at magical-mundane scrapping.

Magically, Between would probably annoy him because it's a lot more fluid than the dimensions and systems he's used to, but he'd also be fascinated watching people work it. He is a magic nerd, after all.

Morally and intellectually he would not vibe with fae culture, nor with Pet's three "psychos" in their earlier appearances. They have an explicit disregard for human deaths that would make him MAD. They're also pursuing a long-term serial murder investigation (focusing on fae murders, though humans have also incidentally died), which he would obviously get into the middle of somehow as an upstanding wizard PI. He would probably solve it significantly sooner, too, I have to say!

Man, that would be messy.

So yeah, watching these fae and vampire tramping through human society and brushing aside the collateral damage their society is causing, all while (inefficiently, as far as he can see) investigating an apparent immortal serial killer? Harry would be feuding with them very early in his own investigation. Hopefully not tipping over into outright war, but the relationship would not be smooth.

Oh! And there's a teenage human girl in their household who keeps trying to get everyone to play nice together. Tripping all his protective chivalry instincts.

He WOULD like Pet. He would be so so stressed about her but he'd respect her moral compass and determination, and try very hard to make sure she could count on him as a human ally. And Pet would appreciate that! She'd need him not to try and get between her and her psychos, because she gets attached to them quickly, but having the option of a human wizard protector who understands all her moral issues would be kinda great.

In conclusion... I think if Harry showed up during City Between canon, he could turn it into a Dresden Files book. I think his resolution to their issues might well be just as good as the way things go in their canon... but differently good. I wouldn't trade that universe for canon but I think it would be fascinating to see.