The Fifth Dimension is an inter-dimensional reality that exists outside of the normally accepted space/time continuum. Due to its five dimensional properties, this reality functions off of a completely different set of physics than those found in typical three dimensional environments.
Zrfff is the home world of a race of impish beings who manipulate the properties of their dimension as a form of "super-science".
The most recognizable denizen of the Fifth Dimension is the troublesome Mister Mxyzptlk. Another famous hero of Fifth Dimension origins is Yz, the Thunderbolt. Yz, who was originally considered a magical genie, is most famous for his adventures with the Justice Society of America in the 1940's.
Points of Interest
- In Earth-One continuity, Mxypolis was a metropolitan city in the 5th Dimension. Mister Mxyzptlk or Bat-Mite patterned it after the city of Metropolis. 
- Zrfff: is a strange world in the Fifth Dimension, home of the creatures known on Earth as "imps" and "genies".
- List of 5th Dimension Inhabitants
- Mister Mxyzptlk
- Miss Gsptlsnz
- Mister Genie (Genro)
- Yz, the Thunderbolt