I can already smell the plot twist with the angels at some point. They either wait for a good moment to strike to enslave the humans after they were weakened by the succubus or work together with the succubus the entire time. It's just too fishy...
Its a 12th clan of succubi born from the seraphim in a 'fight fire with fire' move against the incubus that'll turn around to bite him in the ass. Calling it now.
Speaking of the angels, here is some lore that I wrote about them for the next chapter:
Angels
Angels are a type, and the most prominent, of Divine beings, a Spirit that was attracted by, and took form in, the Soaring Heaven. Angels represented perfection in the eyes of the Universal Architect, Veridatha, who crafted the "Original Seven" or the Seven Heavenly Virtues.
As we comprehend, by exchanges with the angels themselves, before the very formation of this universe that we now inhabit, The Original Seven were used as generals in the holy army against the Original Sin, Ascalon, father of all demons. Therefor, The Seven Heavenly Virtues came from outside our own reality, not have been born into our plane of existence like all the other angels, for example, like the ones that now protect the City of Adalon.
The Original Seven are outsiders, much like the Seven Deadly Sins themselves. The most distinctive characteristics of the angels are their halos and wings, both of solid, hard metal. However, already enchanted with levitation, allowing angels to fly high and quickly without the need of actual wings. Same wings that the pictures and images created by humans describe them so erroneously.
Both the halos and wings of the Original Seven were crafted, instead of being randomly developed like the wings and horns of the chaotic succubi. This emphasizes the love for order and perfect symmetry that the Universal Architect had and his views for his creations. This was passed down to the new generations of angels created in our universe.
Angels are relatively few in numbers compared to the succubi, but are much stronger individually. In the past, a single angel was seen fighting alone against multiple demons and emerging victorious.
There are both male and female angels, but all of them that we encountered to this date were remarkably tall and gorgeous heavenly figures, with a huge diversity of color of eyes and hair, unlike the few human variations we possess.
The only contact we have with the angels are from the ones of the City of Adalon, in the Far South. The city itself is ruled by Raguel, a powerful Archangel. No contacts were made with the Seraphim that leads this army of heavenly beings here in Yrdarvyr. Only its name escaped to our ears. Ramiel.