"Angels of Death Episode.0" serves as a prequel to the main series, delving into the origins of its central characters and the events that shaped their fates. The narrative centers on Rachel Gardner, a 13-year-old girl who becomes trapped in a mysterious, multi-level building after a traumatic incident. Each floor of the building is overseen by a deranged individual, and Rachel must navigate these levels to escape. Along the way, she encounters Zack, a serial killer wrapped in bandages, who becomes both an ally and a threat. Their uneasy partnership drives much of the story, as Rachel’s calm demeanor contrasts sharply with Zack’s violent tendencies.

The manga explores Rachel’s backstory, revealing her troubled past and the circumstances that led to her confinement in the building. Her parents’ neglect and the emotional abuse she endured are key elements that shape her character. The narrative also provides insight into Zack’s origins, detailing his descent into madness and his obsession with killing. The relationship between Rachel and Zack is complex, oscillating between dependency and mistrust, as both characters grapple with their own moral ambiguities and psychological scars.

The supporting cast includes other inhabitants of the building, such as Danny, a doctor with a disturbing fascination with Rachel, and Cathy, a woman who manipulates others for her own amusement. Each character embodies a different facet of human darkness, contributing to the oppressive atmosphere of the story. The building itself functions as a metaphorical prison, reflecting the characters’ inner turmoil and the inescapable nature of their pasts.

The plot is driven by Rachel’s determination to reach the surface and Zack’s conflicting desires to protect her and fulfill his own violent impulses. The tension between survival and self-destruction is a recurring theme, as the characters confront their fears and the consequences of their actions. The manga’s pacing is deliberate, with a focus on psychological tension and character development rather than action. The narrative’s structure alternates between present events and flashbacks, providing a deeper understanding of the characters’ motivations and the events that led them to their current predicament.

"Angels of Death Episode.0" is a dark and introspective exploration of trauma, morality, and the human condition, offering a foundation for the events of the main series while standing as a compelling story in its own right.