Establish a relationship between the convenience and the playful, taking advantage of the material flexibility. The modules allow users to choose the appearance of the bookshelf by adding or removing modules, according to their needs and available space. Modularity also allows playing with shapes and colors. The result may be a bookcase that has one, two, or many colors. Finally, no matter how large or small, high or low this bookcase can be, the fun is to have a modular and flexible bookcase that deforms under the weight of books and objects and can be always changing appearance.