When Everyone Was Fleeing, I Opened a Convenience Store in the Ruins

The red rain falls and the end of the world comes. Everyone thinks rain is fatal, but I am the only one who knows—— The red rain does not hurt people, but it nourishes monsters. The convenience store left by my parents is my only root in the apocalypse. Taking my sister along the way to survive, I met intelligent monsters and mysterious companions. The legend of the shelter is spreading in the wind, but I know—— No matter how safe it is outside, it is not as safe as the home you keep.