@Not!Onnex Ok, I've never critiqued a universe before, and if I'm being honest worldbuilding isn't exactly my forte, but I'll do my best to be helpful. You asked specifically for comments on the premise and exposition, and from what I gathered they are great. I'm not very familiar with many of the concepts you mentioned, like eldritch horrors and dead zones, but from your exposition alone (and also some quick searches on google images) I think I got the general vibe of the story. I really like the idea of this being a cartoon, and I think the concept of a PI agency that investigates crimes (presumably) related to other dimensions clipping with Earth is super fun and would work great as an animated show, so you really nailed it (do people still say that? English is not my native language and I'm terrified of talking like an old lady who wants to be cool with the kids) when choosing the medium. If I could give you any advice when it comes to exposition, I'd tell you to not assume people know what you're talking about, even when It's a fairly well-known concept. I think you did well explaining the dimensions and how this world functions, but I'd suggest you take the time to explain some of the references you use, especially the ones related to Christianity. I'm focusing on that specifically because of how common it is for creators to assume the audience is familiar with Christianity, and as someone who grew up without religion, I guarantee you that's not always the case. Don't get me wrong, I LOVE Christian symbolism in stories, especially catholic when used in a profane context, and I think it matches the general vibe of your story really well, but I also have no idea what a "biblically accurate angel" looks like and if you reference any passage of the bible that isn't Adam and Eve or that one with Jesus and the prostitute I won't have the faintest idea of what you're talking about. You don't need to stop the story to give an extensive explanation every time you make a biblical reference, just make a small comment so the audience knows what you mean. For example, you say on Azazel's profile that xe (I hope I'm using the pronouns the right way but I've never used them before so I'm sorry if it's not correct) is old enough to have been cast out of Heaven around the same time as Lucifer, so if you're going to mention this in the story, just make a small comment about how God? expelled many angels (assuming they were angels idk) from heaven during that time, and maybe the reasons why they were banned if you think it's necessary. And because we are on the topic of religion, let's talk about how it relates to your story for a bit. You say that many mythological/religious characters exist in this universe as eldritch horrors and that many of the stories that we hear about them are misinterpretations of events that occurred due to dimension clippings. This is a very interesting concept, but if it also raises some questions: if humans know about the existence of other dimensions, do they also know that their gods are not actual gods? Is religion still a thing? Do people worship those eldritch horrors as their creators? If the Christian god exists but didn't create the universe, did she do anything that would make people believe she did? Why is she the Christian god? And also the "Christian god" is not exclusive to Christianity so is she also Allah and the god described in the Torah (or any other version of the same god I'm not familiar with? Is Satan a thing? It's not always a thing in Abrahamic religions, sometimes it's a feeling. Was the universe created by a superior being? Or was it the big bang and shit? Do humans have the answers to any of those questions? What do the eldritch horrors who are worshipped as gods think about being worshipped?
Ok, I think that's it! I'm sorry it's so long and confusing, but I tried. If you want to know, I'd watch the shit out of this show, so great job!