"Magilumiere Co. Ltd." is a workplace fantasy anime centered around a magical corporation that employs young women as magical girls to combat supernatural threats. The story unfolds in a modern urban setting where magical energy, known as "Lumiere," powers both everyday life and the dangerous entities that threaten it. The protagonist, Kana Hoshizuki, is a recent high school graduate who joins Magilumiere Co. Ltd. as a rookie magical girl. Unlike traditional magical girl narratives, the series frames their roles as corporate employees, complete with contracts, quotas, and performance evaluations.

Kana, alongside her colleagues, is tasked with neutralizing "Nocturnes," malevolent creatures born from negative emotions and corrupted Lumiere. Each magical girl wields a unique ability tied to their personality and emotional state, emphasizing teamwork and strategy over individual heroics. The narrative explores the challenges of balancing personal growth, workplace dynamics, and the moral complexities of their missions. Key characters include Aoi Tachibana, a seasoned magical girl and Kana's mentor, and Rina Fujisaki, a rival with a pragmatic approach to their work.

The plot delves into the corporate structure of Magilumiere Co. Ltd., revealing its profit-driven motives and the ethical dilemmas faced by the magical girls. As Kana and her team uncover deeper secrets about the origins of Nocturnes and the true nature of Lumiere, they must navigate internal conflicts, corporate politics, and the emotional toll of their responsibilities. The series blends action, humor, and drama, offering a fresh take on the magical girl genre by grounding it in a relatable, albeit fantastical, workplace setting.