The series began in 2016 in Bessatsu Shonen Magazine and has five volumes available in Japan.
The series comes from Naoki Yamakawa and artist Akinari Nao and has had three volumes released digitally in English so far.
Back in July 2018, Kodansha Comics added a digital series to their ranks with 100-man no inochi no ueni orewa tatteiru, which they’ve localized as I’m Standing on a Million Lives for its release.