It feels like you're literally trying to do a fanfic of Jvan.
So let's start with persona this time. Your idea is cool and certainly workable, but the big thing is that whereas Jvan was a 'cancer' upon the world that nonetheless had complex emotion and feelings and contributed by creating things, Anz is seemingly like Xos in that he just wants to destroy and devour literally everything. That's cool but it
really restrains the potential for what you can do, and Anz'll be left with no way to meaningfully interact with the world other than by 'inflicting himself upon it'. After a while that'd start to feel like Groundhog Day; you'd get bored of it and we'd probably also eventually get bored of it. So that's bad and it'd be nice if you added some more depth here. I say make him more like Sauron; he doesn't want to just destroy the other gods and all of their things, he wants to ultimately
remove them and remake the world. And for that means he's willing to
create demons and build up an empire of sorts to accomplish that. Whereas Xos just kills stuff, Sauron contributes to Middle Earth by making cool magical rings, a cool place called Mordor, a cool evil tower, some cool orcs...
Sheol is a decent Sphere. It harvests and reshapes matter itself(?) in order to create soulless demons, and while it doesn't innately have an 'effect' on other Spheres, being the source of the demonic invaders is probably enough to pass as an effect. If we removed Sheol, Galbar would NOT be the same, so your Sphere passes my test. Still, there's potential for you to perhaps do more with it. We like the connection to Ohannakeloi being like an elemental battlefield, but you could probably have connections and interesting boundaries with lots of other Spheres too.
As far as a Portfolio, I like demons. It's really specific and niche, but you can do a lot of different things with different demons and you seem to have plans for doing so. Now, BBeast raised a good point, "The Portfolio needs to be less specific about what demons are. Loki's already revised demons several times already, which is fine, but he'll get stuck if he defines it too tightly from the start. A definition including some of the basic universal traits of demons, things which define what a demon is, is good. A full and total description of their precise functioning and abilities restricts your ability to adapt and change." I think that as of our most recent DM conversation you had a pretty good idea of how demons would work, but you don't need to explain all of the details now. Save it for the IC so that you can be more flexible, as BBeast suggests.
Also, Mutton wants to know what this is supposed to mean, "...Demons are capable of manifesting basic constructs of energy..."
Are you trying to justify them having some sort of powerful innate magic? That costs extra MP but is doable.
Accepted contingent upon you adding a bit of depth to the persona or coming up with some way to make Anz only 99% evil and destructive rather than 100%. Also, because you had to be reviewed last, Mutton's been waiting like two weeks to have that pressing question answered. I'm sure he's dying to know, so you'd better answer him too.