[@BunniesOfDoom] This is a very interesting idea, I love it!
I have a couple of questions:

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[*] Is the snatching of human souls similar to ending their lives and having them reborn as demons or do the victims of the demons also willingly give up their bodies to a new demon? 
[*] How strong are the powers of the Nephilim? Are we talking about regular magic that they have to train or overpowered magic that they aren't able to control due to their physical limitations? Is it the same case for the demons?
[*] Are the demons randomly ending lives as they see fit or have they gathered to find the Nephilim together? 
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