Hambrosians are a species of polydimensional aliens, meaning that they exist on several planes of reality at once.
Their appearances are reminiscent of sea creatures, with fin-like hands and squid-like head-top. They seem to generally have blue skin and yellow eyes.
Being polydimensional, or 'poly', they do not seem to enjoy their stay on Earth, as it appears on only one plane of reality (it does have one more plane where dogs and humans have changed roles, but it was a little "too far-fetched" for Hambrosians taste). And because Hambrosian genitals don't start manifesting until plane ζ, they are unable to form sexual bonds with any humans.
A Hambrosian named X’Ulililir Popoiv wrote an article in a magazine called Nazz about this, titled "Earth Sucks If You’re Poly: a NAZZ Special Report". 
- They appear to be used to being discriminated against
- Their saying, "For the love of Grundis", could point to their God being named Grundis