EMMA BOVARY is the main character in a novel by Gustave Flaubert (1821-1880) entitled Madame Bovary. At the time of its first publication (in serial form in 1856), it caused quite a stir in French society, and was the subject of an obscenity trial in 1857.
MADAME DE GUERMANTES is a character in Vol. 3 of an autobiographical novel in 7 volumes by Marcel Proust (1871-1922) entitled À la recherche du temps perdu (sometimes translated as Remembrance of Things Past and sometimes as In Search of Lost Time). The third volume is entitled Le Côte de Guermantes, translated as The Guermantes Way.