Who is Eva's cat from Collected Stories and what is their importance?

Eva is a beautiful young woman who is dying. Through some sort of witchcraft, her soul is transplanted into her cat in a strange ploy to cheat death in "Eva Is Inside Her Cat." Transformations of men into animals, gods, or demi-gods are, of course, common in folk tales and mythology. Garcia Marquez borrows this ancient device to create a new existential dilemma, thus combining a time-honored literary tradition with the most modern of existentialist worldviews. Eva seems to have made some kind of Faustian bargain to swap souls with her cat, in a vain effort to avoid witnessing her own loss of beauty and decay.