"Gibiate" is set in a post-apocalyptic Japan where a mysterious virus, known as the Gibia virus, has transformed the majority of the population into grotesque creatures called Gibia. These creatures vary in form, ranging from humanoid to monstrous, and pose a constant threat to the remaining survivors. The story unfolds in the year 2030, following a group of individuals who must navigate this dangerous world while seeking a cure for the virus.

The narrative centers on two main characters: Kenroku Sanada, a skilled samurai from the Edo period, and Kathleen Funada, a ninja from the same era. Both are transported to the future through a time-traveling phenomenon, finding themselves in the midst of the Gibia outbreak. Alongside them is Dr. Yoshinaga, a scientist dedicated to finding a cure for the virus, and his assistant, Yuka. The group also encounters Sensui, a mysterious warrior with his own agenda, who aids them in their journey.

As the story progresses, the group faces numerous challenges, including battles with the Gibia, internal conflicts, and the moral dilemmas of survival in a world where trust is scarce. The narrative explores themes of resilience, cooperation, and the human condition under extreme circumstances. The characters' backgrounds and skills from their respective eras play a crucial role in their survival, with Kenroku's swordsmanship and Kathleen's stealth proving invaluable.

The plot is driven by the group's quest to find a cure for the Gibia virus, which involves uncovering the origins of the outbreak and confronting those who may have played a role in its creation. Along the way, they encounter other survivors, each with their own stories and struggles, adding depth to the world-building. The series balances action-packed sequences with moments of character development, providing a comprehensive look at the challenges faced in a world overrun by monsters.

"Gibiate" presents a blend of historical and futuristic elements, with the juxtaposition of Edo-period warriors in a dystopian future serving as a unique narrative device. The series maintains a focus on the central goal of finding a cure, while also delving into the personal journeys of its characters as they adapt to their new reality. The interplay between the characters' pasts and their present circumstances adds layers to the story, making it a multifaceted exploration of survival and hope in the face of overwhelming odds.