You can find the latest chapters and archives on the official Yanmaga Web platform.
As the series progressed past Chapter 250 (it eventually surpassed 300 chapters), the narrative shifted from survival within the prison to more complex external missions and deep conspiracies.
: The story follows Chiko Amagi, a normal girl who is sent to a high-security prison after being infected with "Medusa Syndrome," which turns girls into ruthless killers.
The series heavily features extreme violence, psychological horror, and mature themes, including gore and nudity. Guide to Approaching Chapter 250
You can follow the latest official updates and chapters through legitimate manga platforms and publishers: The official Japanese publisher for the series.