That doesn't seem to be an angel. more like some kind of order guardian. like on an other axis: not (evil - good), but (order - chaos) It would work with there being chaotic beasts imprisoned in the lake guarded by one of them.
Maybe we could push some orderly evil into her(?) system and corrupt her(?)?
Also: one of the Chaos Creatures was killed by the Order Creature and bled into the lake. Have A Wounded Cultist drink that water to see if they mutate and are functional again. Everybody likes some tentacles, right?
There doesn't really seem to be another axis in this setting. Good and Evil are both measurable energies and can be expressed/generated in orderly or chaotic ways - just look at the difference in how we've been playing Nokluvgn versus Krnlrklr Yrlvnt. Good isn't necessarily nice to mortals, just as evil isn't necessarily always murderkillmaimsacrifice.
Plus the whole gender thing. The fact that Nokluvgn knew it was a she on sight, plus the only angel quest spinoff the original Demonhood got had a female angel ... not a hard conclusion for me to draw. Even if it isn't, we can't let it escape.