In the year 2030, a pervasive virus called 'Gibia' ravages Japan and spread across the globe, causing individuals to turn into monstrous creatures based on their age, ethnicity, and gender. Due to its significant diversity, the virus got its name 'Gibia.' Amid this apocalyptic setting, a formidable duo of a samurai and ninja from the Edo era unite with a doctor to discover a remedy for the Gibia virus. As they trek through a treacherous wasteland, they encounter constant attacks from Gibias and marauding bandits, preying on the vulnerable for survival. Despite the formidable dangers and the abundance of adversaries, they bravely forge ahead on their perilous journey, unfazed by the looming threat.