The design of this shelf refers to the Hako kaidan or Kaidan dansu, a traditional Japanese piece of furniture that works both as a ladder and a storage structure. The Japanese kaidan dansu is not only a multifunctional object, it is also an actor that has been very present in domestic spaces throughout history, accompanying and supporting the political, social and cultural transformations of this country; and it is also present in popular myths. Originally, the haikan dansu was a simple open staircase, which was later closed with boards underneath the steps. According to a Japanese legend, the reason for this adaptation was mainly practical: they wanted to prevent the samurai's sword from reaching them when escaping to the upper floor. Gradually, it became a piece of furniture-storage-staircase. Its formal evolution is full of stories and nuances, some probably the result of legends, others derived from questions of class differences, practical reasons such as the camouflage of first floors, architectural pragmatism, or typological differences depending on whether its author was a carpenter or a cabinetmaker, etc.