built-in bunk / loft. I can visualize this as a larger studio apartment for an adult, with a home office (or a storage area) above the bed. Pull the doors shut during the day and the bed will disappear, and the office will have a loft-like appearance.
Small House Folding Interior - Japanese designers Atelier OPA created a unique set of products, which are perfect for small spaces. Includes a mobile home office, a small kitchen, and a guest room (pictured). When not in use, fold your furniture away.