Rat people are a group of genetically modified humans from Kalliope with distinctively ratlike features.
During experiments by Fairchild Research and Development on the planet Kalliope, they spliced rat genes into already-living people. The aim was to create people who could burrow underground during Kalliope's violent earthquakes. These people were deeply mistreated by Fairchild, and then discarded once Kalliope became liveable. As such, some militant rat people have formed the Odamas Fleet to take the planet back for themselves.