Gibiate takes place in Japan in the year 2030, when humanity has been infected with a brand-new virus named Gibia that has spread across the globe. The Gibia virus turns humans into different monsters known as Gibias, which change based on a person's unique traits, such as age or gender. One day, in the wasteland of polluted Japan, a time-traveling samurai and an Edo era ninja show up. Together with a doctor, they look for a cure while battling both the infected and lawless criminals looking for sustenance. The start of a perilous trip filled with grave perils.
