A major theme in the series is the concept of "God" as a source of salvation and validation.
: As the story progresses, Rachel’s devotion shifts from an abstract deity to Zack himself. She begins to view him as her personal "God" because he holds the power over her life and death. Satsuriku no Tenshi
: The character Abraham Gray treats the entire building as a testing ground for human nature, using hallucinogenics and trials to push Rachel toward a "confession" of her true self. Character Arcs and Shared Trauma A major theme in the series is the