As their debut single is called 'Nightmare', each girl represents a different nightmare. Yoohyeon's nightmare represents being lost at a strange place.
Happyface Entertainment explained, "The two versions of the jacket photos that are being revealed draw two sides, of being a girl and of being a nightmare. It tells Dream Catcher's single and album's story as a summary."
Dream Catcher will debut with "Nightmare" on the 13th!