In 2030, Tokyo. A disease named GIBIATE has infected humans throughout the world. Infected people turn into different forms of monsters (Gibia) based on their ages, sexes and races.
Kanzaki Sensui and Sanada Kenroku, a samurai and a ninja who have traveled through time from the Edo period, met Kathleen Funada- a doctor's assistant. Then the story begins.
What will happen to Sensui, Kenroku, and the others as they face the monsters (Gibia) for the first time?