The story is set in five closed worlds, nicknamed “Disaster Worlds.” Kuro is an invisible girl that comes from outside these worlds, and Hyouma is a boy who can only see invisible people. To alleviate their loneliness, the two get close, but “disaster” eventually bares its fangs and a cruel world stands before them. This is a story of sadness and overcoming that begins with a meeting that has not happened yet, but is inevitable.