Really small, 6m² room with the only function as sleeping. There is just enough space for your luggage and personal belongings and yourself.
I recommend it for solo travellers, or couples who only need a bed after a busy day in Amsterdam. Due to the tilted ceiling, tall people might have difficulties, need to be careful not to bump your head.
Pros: isolated, silent, next to the bathroom, and gives a really cosy feeling inside.