"Puella Magi Kazumi Magica - The Innocent Malice" is a spin-off of the "Puella Magi Madoka Magica" franchise, written by Masaki Hiramatsu and illustrated by Takashi Tensugi. The story centers on Kazumi Subaru, a magical girl who awakens in a suitcase with no memory of her past. She is discovered by a group of magical girls known as the Pleiades Saints, who take her in and claim she is their friend and fellow member. Kazumi struggles to reconcile her amnesia with the fragments of her identity that occasionally surface, including violent impulses and unsettling memories.

The Pleiades Saints, led by Umika Misaki, are a close-knit group dedicated to protecting their city from witches, monstrous entities born from despair. They also operate a secretive side project: harvesting grief seeds, the remnants of defeated witches, to create a substance called "Soul Gems," which sustain their magical abilities. Kazumi gradually learns that the Pleiades Saints are not merely fighting witches but are also involved in morally ambiguous experiments to create artificial magical girls, raising questions about the ethics of their actions.

As Kazumi integrates into the group, she begins to uncover disturbing truths about her own existence. Flashbacks and encounters with other magical girls reveal that she may be an artificial construct, pieced together from the remains of deceased magical girls. This revelation ties into the Pleiades Saints' broader goal of resurrecting a fallen comrade, Airi Anri, whose death haunts the group. Kazumi's internal conflict intensifies as she grapples with her identity, her violent tendencies, and the possibility that she is merely a tool for the Saints' ambitions.

The narrative explores themes of identity, morality, and the consequences of tampering with life and death. Kazumi's journey is marked by her struggle to define herself beyond the expectations and manipulations of others. The Pleiades Saints, while initially portrayed as benevolent, are revealed to have their own flaws and motivations, blurring the line between heroism and selfishness. The story culminates in a confrontation with the true antagonist, a powerful witch born from the despair of a magical girl, forcing Kazumi and the Saints to confront the consequences of their actions and the fragility of their existence.