User blog comment:Crimson and Darkness/Volume 25 discussion blog/@comment-2601:8C:601:5692:6CC6:6C09:CEA1:B2ED-20180321212211/@comment-2601:8C:601:5692:6CC6:6C09:CEA1:B2ED-20180321222726

Continuing on, interesting info from Slashdog Vol 2:

Khaos Brigade was originally formed by the rogue Grigori leader (fallen angel) Satanael and his students/disciples who were formerly members of "Nephilim Abyss", also known as the "Abyss Team", a sub-group of Grigori's "Nephilim" consisting of heinous Sacred Gear users.

Lavinia (17, now 21) was for 4 years the disciple of the "Witch of the South" Glinda from the mage group "Wizards of Oz", who discovered her as an 9-year-old orphan while investigating Sacred Gears in the world. She was transferred to Grauzauberer at the age of 13 as part of an interchange program. Walburga was the disciple of the second generation "Witch of the East" Augusta.

"Oz", which is a dimension created in the dimensional gap and maintained by the power of the four witches from their castles and the group's boss (presumably the Great Wizard) from the Emerald City at the center. The group is comprised of mages/magicians who desired to focus completely on magic without interference, and suffered infighting until recently (as of Slashdog, set 4 years before HSDxD). They seek (?) the Three Demon Beasts: Cowardly Leo, Dead Lumberjack, and Rampage Scarecrow.

Himejima Suzaku (17, now 21) looks a lot like a "darker version" of Akeno based on her picture. She uses shikigami, excels at flame jutsu, and knows taijutsu.

Ouryuu's predecessor was known as Nakiri Nakagami no Ouryuu.

In addition to Minagawa Natsune (Qióngjī) and Samejima Kouki (Táowù), the remaining Four Fiends holders are Nanadaru Shigune (Tāotiè), who joins Nephilim, and Koga Hyousuke (Húndùn), who has not as of volume 2. Tobio's childhood friend, Toujou Sae, also joins Nephilim.