I built my own magical girls setting, with soul exaltation and polytheism.

At some point this will contain a link to the actual setting document, but TLDR:

Magical People
- magical people can be of any gender but usually get magic in their teens; they're a small but slowly growing percentage of the population and the "growing" part isn't just because they can become immortal if they play their cards right
- magic consists of the ability to shapeshift into a customisable magical form (magiform), plus an individual themed set of personality-based powers the strength of which are based on how much your magiform reflects your inner self at any given time
- time spent in magiform runs down a magical resource we might as well call "charge"
- you accumulate charge by doing things that are soul-exalting, which is the only magical thing you can do in your regular form
- it's possible to reach escape velocity on charge and spend all your time in magiform, at which point you become immortal because magiforms don't age

Other Setting Details
- not an Earth, but similar in that it has humans and no other intelligent species unless you count centaurs
- some mythological animals, such as griffins and winged horses, exist; the only ones smart enough to talk are centaurs and they're not very smart
- roughly 20th or 21st-century tech level but with minor differences in the exact tech tree
- solar power is the standard form of electricity generation
- smartphones evolved from pocketwatches and are therefore called smartwatches
- the focus country is called Azama, capital Corali
- names in Azama go family name + given name
- the dominant religion is polytheistic and has 7 gods