Takashi Tensugi: 5 books

Trapped inside the witch's barrier with the vengeful Kanna, Umika and Kaoru struggle to protect Kazumi as their beloved friend slowly succumbs to her darkening soul gem. If the girls can rally, the witch's grief seed could be used to purify all of their gems, but even that would be only a temporary...

From the very start, it was Kazumi who drew the girls of the Pleiades Saints together. But no magical girl, however beloved by her friends, is exempt from the fate that awaits them all. Fearing that the evil nut may be accelerating Kazumi's transformation, the girls are divided - can the process be delayed, or should they take out Kazumi while they still can?

Kidnapped and stuffed into a trunk by an unknown assailant, teenager Kazumi bursts forth from the confines of the case to discover that she has been stripped not only of her clothes, but also of the memories of her life before the kidnapping. When she is recovered by a pair of schoolgirls, she doesn't...

Kazumi is determined to continue to battle witches alongside the Pleiades Saints, a group of Magical Girls who were Kazumis companions prior to losing her memory. But it turns out that the witches aren't her only enemy... Yuuri, a Magical Girl, has turned against her own kind and targeted the Pleiades...

As her teammates look on in horror, Niko succumbs to the taint that has overwhelmed her soul gem and she transforms into a terrifying witch. But there is little time for the Pleiades Saints to grieve-this new witch has gone on the attack! Left with no alternative, Mirai strikes down her friend to save the rest of the girls. Is there any power that can save the Magical Girls from their fate?