Their natural form appears like a purplish mass with several tentacles, and they are able to cling on to walls. Like most cephalopods they are able to change the color of their skin depending on their emotional state.
They are an extremely naïve and kind species, and are notable for having no concept of fiction, or deceit. As a result, they have mistaken broadcasts of Earth TV shows for "historical documents", in particularly Galaxy Quest and Gilligan's Island.
Information on the Thermians' early history is scarce, but in the 5 million years following the Great Nebulae Burst, their people were unified. And they eventually came into conflict with the Sarris Dominion, which wiped out most of their population and left them without a world of their own.
At some point they began to receive transmissions from Earth, and they remodeled their entire society based on the television program Galaxy Quest. Because of their naïve nature they failed to fully understand the program, believing it to be a historical document.
Thermian technology seems to be for the most part modeled after what they have seen on the television show Galaxy Quest.
Their technology is highly varied and advanced: they have food replicators, organ fabrication devices, and more notably are extremely adept at interstellar travel. Their devices allow them to alter their appearance to look human, although they may still exhibit strange mannerisms and speech patterns, and can still expose their tentacles.