Planet FM

Planet FM is a fictional planet from the Mega Man Star Force series. It is home to the FM lifeforms, or FM-ians, a race of aliens who have electromagnetic bodies who usually bear the names of constellations and feed on human negative emotions. They are the main villains in the first installment, having destroyed the similar Planet AM and planning to destroy planet Earth due to their king Cepheus' paranoia. However, some of them are not evil, and by the end their king decides to halt his actions and make up for his crimes.

The planet itself appears to be covered in EM Waves, which it emits into space.

Trivia

 * Planet FM may be named after Frequency Modulation.