"Chirality" is a manga series set in a dystopian future where humanity faces extinction due to a deadly virus known as the Mistletoe Virus. The virus primarily affects men, leading to a severe gender imbalance and societal collapse. In response, the government establishes the Special Anti-Epidemic Unit (SAEU), tasked with combating the virus and maintaining order. The story centers on two main characters: Ryou, a young man who becomes infected with the virus, and Kaoru, a member of the SAEU who is assigned to monitor and protect him.

Ryou's infection places him in a precarious position, as the virus grants him enhanced physical abilities but also makes him a target for those who fear or seek to exploit his condition. Kaoru, initially cold and professional, gradually develops a deeper connection with Ryou as they navigate the dangers of their world. Their relationship becomes a focal point of the narrative, exploring themes of trust, survival, and the ethical dilemmas posed by the virus and its treatment.

The plot unfolds as Ryou and Kaoru encounter various factions, including rogue scientists, government agents, and other infected individuals, each with their own agendas. The SAEU's methods of containing the virus often blur the lines between protection and oppression, raising questions about the morality of their actions. As Ryou struggles with his identity and the implications of his infection, Kaoru is forced to confront her own beliefs and loyalties.

The series delves into the psychological and emotional toll of living in a world ravaged by disease and societal breakdown. It examines the complexities of human relationships under extreme circumstances, as well as the broader implications of scientific experimentation and governmental control. The narrative is driven by a combination of action, suspense, and character development, with a focus on the evolving dynamics between Ryou and Kaoru as they face both external threats and internal conflicts.