Takahiro and Toru launched the spin-off manga in Square Enix's Monthly Big Gangan magazine in October 2013. Takahiro does the story while Toru is in charge of illustrating the manga.
Synopsis of Akame ga KILL! ZERO:
The "dark action" manga takes place a few years before the events of Takahiro's original manga series, Akame ga KILL! This prequel focuses on the main character, Akame, a bought girl, who was brainwashed and raised by the Empire as an assassin.
The mangakas began serializing the original Akame ga KILL! in Square Enix's Monthly Gangan Joker magazine in 2010 and concluded in December 2016.
The manga had an adaptation to an anime series that premiered in Japan in July 2014. Crunchyroll aired the anime while it aired in Japan. The series aired on the Adult Swim Toonami block beginning in August 2015.
Source: Akame ga KILL! ZERO volume 9
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