Azusa, who is about to take college entrance exams, attends summer classes, so she does not go on a family trip and stays home alone. Worried about it, her parents ask her relative's older sister to stay away with her. That night, a severe lightning strike causes a power outage and darkness descends. The room is steamy with no air conditioning. The two hug each other in fear of a lightning strike and gradually sweat. Before long, the smell of sweat drives them crazy...
