An unknown event has split the world in two, reshaping it into something entirely unlike its original form. In a bright corner of the city, a group of girls stays close together, unaware that their own existences have been cut in half. They're only half of who they're supposed to be. Hoping to find their true selves again, they journey through various worlds and run into strange phenomena tied to rumors of people called urban legends. The ONA mixes mystery with the supernatural.