Bunk beds are usually the mainstays of most people trying to get as many beds as possible into a room. What makes the space on the photo above unique, however, is the bunk bed and the mattress placed under the window. Simple wiring helps protect the highest possible space from falls. Again, using the window helps the highest sleeping space to feel less cramped. In addition, access to the upper sleeping area by a ladder leading to the bunk bed gives the space a playful design on three levels.
It also proves that you can use all parts of a space in a fun and functional way. Usually, areas with a steeply pitched roof become regulated or not even used at all.