Souls to Ash

Kame Shohei is a normal girl, intelligent, loyal, and kind, or so she thought until a witch, magical girls' main prey and predator, takes away everything she ever loved.

Now she's the proud leader of Namari, a team of elite magical girls, also known as magi. However elite they are believed to be, they still work beneath Tezuka and her team known as Zenryona. They, alongside many other groups of magi work to keep each other alive within a society of many other girls broken and defeated just as Kame had been, left no where to go, they banded together and vowed to protect each other until the end. As nice as it may seem, everyone has dark secrets that must never be shared.

What happens when these secrets become known to the head chair of the society?
Why did Kyouko Sakura leave the society for Mitakihara?
Why does the society seem so hostile to others, but so kind to one another despite hardly knowing each other?

I'm not sure myself, you'll have to read to find out.