"Fabricant 100" is a manga series set in a world where artificial humans, known as Fabricants, are created to serve humanity. These beings are designed with specific purposes, ranging from labor to companionship, and are often treated as disposable tools. The story centers on Ashibi Yao, a young man who encounters a unique Fabricant designated as Number 100. Unlike other Fabricants, Number 100 possesses a level of autonomy and emotional depth that sets her apart from her counterparts. She is on the run from her creators, who view her as a dangerous anomaly due to her advanced capabilities and self-awareness.

Ashibi becomes entangled in Number 100's plight after she saves his life, and the two form an uneasy alliance. Together, they navigate a society that views Fabricants as mere objects, while evading the relentless pursuit of the organization that created her. The narrative explores themes of identity, humanity, and the ethical implications of creating life for servitude. Ashibi and Number 100's journey is marked by encounters with other Fabricants, each grappling with their own sense of purpose and existence, as well as humans who either exploit or sympathize with their plight.

The series delves into the moral complexities surrounding the treatment of artificial beings, questioning the boundaries between creator and creation. Ashibi's evolving relationship with Number 100 serves as the emotional core of the story, highlighting the potential for connection and understanding across the divide of humanity and artificiality. The plot is driven by their struggle for survival and the broader societal tensions that arise from the existence of Fabricants, culminating in a narrative that challenges preconceived notions of life and autonomy.