"The Magic Skin" also known as "The Wild Ass's Skin" is Honoré de Balzac's 1831 novel that tells the story of a young man, Raphaël de Valentin, who discovers a piece of shagreen, in this case a rough untanned piece of a wild ass's skin, which has the magical property of granting wishes. However the fulfilment of the wisher's desire comes at a cost, after each wish the skin shrinks a little bit and consumes the physical energy of the wisher. "The Wild Ass's Skin" is at once both a work of incredible realism, in the descriptions of Parisian life and culture at the time, and also a work of supernatural fantasy, in the desires that are fulfilled by the wild ass's skin. Balzac uses this fantastical device masterfully to depict the complexity of the human nature in civilised society. (Goodreads)