It's worth noting that while some people think Dib and Mr. Dwicky probably took a random name when they contacted Zim without knowing that "Plookesian" was an actual race, the fact that they used a translator with set languages makes this unlikely.
They either have their head in the middle of their body and arms on the top, or the only organic section is the head with the rest of the body being some kind of robotic suit or cybernetic enhancements.
They also seem to be very easygoing and polite even when Zim demands "Superweapons." The Plookesians never said they would give these to him, but they give him some they have laying around just to be nice. They display a happy-go-lucky but mildly sarcastic sense of humor (at least this is true for the two representations of the race we get to see).
For example, when Dwicky asks if they use their ship to "fly through the stars", Mooshy sardonically informs him that in a literal sense "flying through the stars would be pretty stupid, man! But, yeah, we fly around." However, they show no hostility or judgement toward the human race, and kindly allow him to join them when he asks to travel with them through space. Thus, Mr. Dwicky happily leaves Earth with the Plookesians aboard their starship.
|Species of Invader Zim|
|Blobs • Brain-Eating Parasite • Hogulus • Humans • Irkens • Large-Nostril People • Martian • Meekrob • Nhar-Gh'ok • Planet Jackers • Plookesian • Rock Species • Screwheads • Slaughtering Rat People • Vortian|