Set in modern day London, the story takes place in a world where "Shadows" are born from human fear and anxiety. A young girl arrives to study abroad, only to be caught in a bizarre incident as she enters university. In a city with no acquaintances, the helpless girl wanders into "Café Forbidden," a mysterious café that exclusively opens at midnight. She meets an assortment of handsome men employed at the café, where guardians who protect the boundary between humans and shadow convene.