There was this kind of a demon in Slavic mythology called 'poludnica' in Polish. It can be translated as lady midday but I prefer original name. Poludnica was the soul of a woman who died before, during or just after her wedding. She could have been spotted in the noon of hot summer days. Depending on local believes she was telling riddles, killing or maiming her victims, strangling sleeping peasants or kidnapping children playing near the field border.