Alien (My Best Friend Is Invisible)

The aliens are an unnamed semi-humanoid species who resided on Earth after conquering it, adopting a Human-like society.

Biology
Members of this species have two heads with five red eyes, with the tops of their heads being covered in tendrils, antennas and suction pods rather than hair. The also have several long arms, and their skin is grey.

History
At some point, the species invaded Earth and enslaved Humanity. Most of Human race were exported to their interstellar colonies, however some Humans developed invisibly tech to remain on Earth hidden from the invaders.

The aliens proceeded to live on Earth in manner nearly identical to that of Humans. It is not really explained if their nearly identical lifestyle too Humans was either something they already had prior to their arrival to Earth, or that merely stole this lifestyle from actual Humans is unknown, and it isn't clear if former/latter or both are true.

Appearances

 * "My Best Friend is Invisible", by R.L. Stein (1997)
 * Goosebumps, s02e03, "My Best Friend is Invisible" (1997)