Before the Rain Stops

In 2036, a heavy rain changed the world. An unknown virus was mixed into the rain and came into contact with people's skin, turning people into walking corpses, commonly known as zombies. This is a story that takes place three years after the end of the world. The army of zombies is gradually growing, constantly compressing the living space of humans. Facing zombies that can mutate and enhance, where will humans, who can only rely on technology, go?