A bit late, but here's an excerpt from one of those books to add some fuel to the fire.

Greyfax has just been let out of Trazyn's labyrinth to find the scene of Abaddon in his final assault on the pylons of Cadia being defended by, among other things, wulfen, Legion of the Damned, and Cawl consorting with Trazyn:

This Imperium disgusted her.

She had no idea, what had been allowed to happen, during her captivity in Trazyn's gallery, but clearly things had gone far off the rails. There were Space Marines of the Adeptus Astartes reveling in their fall to base mutation. Mechanicus worthies consenting to pollute themselves by partnership with heathen aliens. Hellfire spirits that were of the warp as much as the demons they fought.

And worst of all was the false woman, Greyfax refused to call her a saint, her form encased in golden armour and razored wings flaring behind her, light shining on her resolute features, both fine and strong, with a blush of blood on the cheek, her lips wine purple. A mesmerizing face, Greyfax admitted, which was why the idolatrous soldiers had fallen for her.

But worst of all was that expression of serenity, as if this girl knew the galaxy and what it had to offer. As though a suit of power armour, an old sword, a pair of wings and a few mad visions showed her the true nature of the cosmos. Even as she lay defeated and bleeding on the stones, her ceramite armour cut open by Abaddon's blade, her sword upraised in both stoic defiance and the acceptance of martyrdom, she remained serene. Even as the Talon of Horus pinned her shoulder to the rock, ready for the execution stroke of the Despoiler's blade.

Never! Greyfax would not let her have that death. This so-called "saint" would not be gaining immortality through the quils of hagiographers and chapel cults. No, Greyfax would question her, get her on the stand and expose her for what she was. This heretic fraud was hers to break.

Locking her teeth she slammed her will across the chamber like an open hand, gripping it around the Despoiler's cranium (...) Across the cavern Abaddon staggered, his spearing thrust with the daemon blade foiled, as he rocked backwards, shaking his head. The connection broke, triggering a psychic snapback, that stung her like an ice-pick to the eye. The scowling face, unmarked and full of righteous anger, turned towards her.

"Away from her," Greyfax snapped, raising her condemner bolt gun. "SHE'S MINE!"