This is pretty nice and i quite like it already, but i have one major nitpick:
I am talking about Kate & Iris (from TM), they have basically the same personalities here. For new players, this is gonna be cool, but for returning ones - not so much. It's a bit better for Kate, but Iris is basically a "what if Iris but vampire", with her personality & appearance almost unchanged (at least atm).
What's not so ideal about this:
Even if you love and cherish those characters, or just mostly like the models and want to share/lessen the workload (idk the reasons, do forgive me if i am wrong), they still feel kinda... recycled? maybe even stale?
Basically, folks who came here for the new story, world and chars, they will get a new background (so to speak) but with the old faces all around, and that can get fairly boring and stale - esp without any meaningful (and distinct from TM) chara dev - and that's p bad for any story out there.
But since that's your decision to make (and a core one at that) i won't suggest changing the models/personalities, basically replacing those two chars, it absolutely won't hurt making em different enough, though:
Giving them some different sides, depth which TM ones were kinda lacking, some cool backstory & role in the plot, or maybe even make em evolve into a different person, which should be doable, given enough time and plot beats, for example.
All those things can either alleviate this problem or even solve it for the most part, which would be p cool since quite frankly those two as they are right now are quite distracting here - they were absolutely fine in TM, ofc.
And truth being told, i quite liked TM for what it was - and i hope this one goes above and beyond it! - so good luck to ya OCN, congrats on releasing and beginning a new story, and don't ever give up~ all my criticism comes from the place of love & a wish to help this story be as good as possible, which it deserves since it got quite some potential, imo.
Anyway, hope that helps and won't discourage you from writing and creating something you enjoy and love doing, which is a p cool thing if you think about it.