The Romypo (Syteizon, named after a mythical beast from Africa and India) is a mammal-like pet from the planet Zariki, formerly home to the sentient species called Zarikilen, who were eradicated in an AI uprising before achieving interstellar flight. The AIs were later wiped out by the Revised to avoid their achieving interstellar travel and attacking other sentients.

A romypo is about the size of a loaf of bread and is covered in a iridescent coat of soft setae when it is relaxed. When the romypo is angry or threatened, the setae stiffen explosively into brightly-color spines. It has a foot-long proboscis ending in a sharp beak, which it can unfurl at great speed to snap up the small, crawling creatures that form most of its diet. Its six legs end in large claws used for holding onto the groves of towering plants that grow on its home planet, and it has two tail bumps at the back of its body that can display spines in a fan as a mating display. Its three eyes give it excellent trinocular vision for navigating its native environment.

In the wild, romypo communicate through the forests with loud, barking calls. These vocalizations are often despised by neighbors of romypo owners.

Domesticated as pets for the Zarikilen, romypo were later taken off-planet and genetically engineered into three distinct breeds to be sold as pets to different types of sentients, including humans. The modified romypo were also bred in a range of brilliant colors. The three breeds vary slightly in terms of diet, tolerance of different gravity levels, and other features.

While romypo can be affectionate and comforting pets, they tend to be nervous around strangers, so that their barking and spines are the features most associated with them by non-owners. Their reputation for being loud and annoying is such that the joke is that the Revised wiped out the Zarikilen as punishment for domesticating the romypo.