Satanophany

Satanophany (サタノファニ) is a Japanese manga series written and illustrated by Yoshinobu Yamada. It started in Kodansha's manga magazine Weekly Young Magazine in March 2017. It finished in the magazine in July 2023, and moved to the Yanmaga Web website and app in September of the same year.

Plot
A phenomenon called Medusa Syndrome sweeps across Japan, causing seemingly ordinary young women to develop murderous split personalities, while having no memory of what their murderous personality does. Chika Amagi is nearly raped when her Medusa Syndrome kicks in and she kills the attackers. She is disowned by her parents as she is arrested and sentenced to Haguro Island Prison along with other sufferers of Medusa Syndrome. Once there, she struggles to survive as the corrupt staff encourages the girls to trigger their murderous personalities so they can fight and kill each other.

Publication
Written and illustrated by Yoshinobu Yamada, Satanophany started in Kodansha's manga magazine Weekly Young Magazine on March 13, 2017. In July 2021, it was announced that the manga had entered its final stage. The series finished in Weekly Young Magazine on July 28, 2023, and moved to the Yanmaga Web manga website and app on September 6 of the same year. Kodansha has collected its chapters into individual volumes. The first volume was released on June 6, 2017. As of April 5, 2024, 29 volumes have been released.