What metaphors are used in Aura by Carlos Fuentes?

On Aura's wall is a black cross with a black Christ crucified on it: a metaphor for subversiveness. Since Consuelo, and therefore Aura, engages in various sacrilegious rituals, its presence is probably meant as a mockery of Christ. It is significant that the crucifix is black, for it reflects the dark, gloomy nature of Consuelo's religion.