Ego Rooms are virtual spaces where people store their memories. It is an abstract representation of its owner's mind; its specific design is comprised of cubes, platforms and cables, not unlike the representation of a Memory Remix's process. The Ego room is an arena of mental control and prowess for characters like Madame, who can manipulate the environment's every design with the power of her thoughts.
Ego Rooms are not limited to human users alone. Sentient programs like H3O can create their own Ego Rooms and manipulate them as easily as any human user. H3O's Ego Room, in particular, is comprised of the painful memories given to him by a young Nilin Cartier-Wells and the memories of Sensen abusers, such as Leapers and Memory Junkies.