"100 Banme no Saru" is a manga series written and illustrated by Kawachi Izumi. The story revolves around a young man named Saru, who is the 100th clone in a series of genetically engineered individuals created by a secretive organization. These clones are designed to possess extraordinary physical and mental abilities, making them superior to ordinary humans. Saru, however, is considered a failure by the organization due to his lack of compliance and rebellious nature. Despite this, he possesses a unique trait: an overwhelming desire for freedom and individuality, which sets him apart from his predecessors.

The narrative begins with Saru escaping from the facility where he was created, determined to live a life free from the control of his creators. His journey is marked by encounters with various individuals, both allies and adversaries, who either seek to exploit his abilities or help him evade capture. Among these characters is a young woman named Aoi, who becomes a key figure in Saru's quest for freedom. Aoi is initially unaware of Saru's origins but gradually becomes entangled in the conflict between Saru and the organization pursuing him.

As the story progresses, Saru's past and the true nature of the cloning project are revealed. The organization's motives are driven by a desire to create a new breed of humans capable of advancing society, but their methods are ethically questionable, involving the suppression of individuality and the exploitation of the clones. Saru's defiance challenges the organization's authority, leading to a series of confrontations that test his resolve and abilities.

Themes of identity, autonomy, and the ethical implications of genetic engineering are central to the narrative. Saru's struggle to define himself outside the parameters set by his creators serves as a focal point for exploring these themes. The series also delves into the relationships between Saru and those he encounters, highlighting the impact of his actions on their lives and the broader implications of his existence.

The plot is driven by a combination of action, suspense, and emotional depth, with Saru's journey serving as the primary narrative thread. The series balances moments of intense conflict with quieter, introspective scenes that provide insight into the characters' motivations and the moral dilemmas they face. The interplay between Saru's quest for freedom and the organization's relentless pursuit creates a dynamic and engaging storyline that keeps readers invested in the outcome.