In the age of material abundance, spiritual satisfaction has become the public expectation. This project is designed for a family of three. The concept of a cave is formed through a "large installation", which increases the amusement while solving the problem of spatial movement. In the pattern transformation, we made subtractive processing, turning the original two bathrooms into a multifunctional separated toilet, washing area, toilet area and shower area, so that the use of comfort of residents greatly improved. In style shaping, we used a more unified and seamless rock resistant material, so that the whole space can present the soft and comfortable cream color.