Aliens have landed on Earth and are coexisting with humans in the 21st century. Chigasaki Mayuko, a financially challenged student residing in the quiet town of Enohana, shares a dwelling with NieA, an alien belonging to the lower class known as "Under Seven." Despite Mayuko's efforts to make a living, NieA displays no regard for the outcome of her behavior. The pair's unconventional dynamic creates unexpected friction while the presence of a destroyed alien spaceship lingers in the background.