The Kwi represented the devolved descendants from the saurian Kwa—the original sentient inhabitants of Dathomir.

These Kwi were sizable, two-legged reptilians characterized by their robust rear limbs and diminutive forelimbs. Their skin exhibited a pale blue hue, overlaid with scales of a cobalt-blue shade. The scales situated atop their heads displayed an opalescent quality, often appearing almost lavender in color. A Kwi's face was distinguished by a pair of crimson-colored eyes, a mouth filled with black, spade-shaped teeth, and an elongated, black tongue. Their physical structure enabled them to achieve remarkable speeds. To initiate a sprint, the Kwi would lower their heads and extend their tails directly behind them, utilizing them as a counterbalance. A typical Kwi individual measured three meters in height and four meters in length.
As the devolved progeny of the sentient Kwa, the Kwi lacked the capacity for complex language. Nonetheless, they retained the ability to communicate through a variety of vocalizations. For instance, a honking sound served as a means for a Kwi to summon others. When traversing the plains in groups, individuals positioned at the periphery would emit snorts and grunts to convey instructions. If the leading reptiles produced contented grunts, the herd would maintain its current trajectory; however, if they snorted two or three times on one side of the group, the herd would deviate away from that direction. Furthermore, the Kwi could interact with specific members of other species, provided those individuals possessed psychic abilities that resonated with the Kwi's own.
In the year 31 BBY, a significant number of Kwi were brutally killed by the Nightsisters as they sought to unlock the secrets held within the Infinity Gate.
The surviving Kwi retreated into the desert regions, eventually forming tribes such as the Blue Desert People, the Blue Mountain People, and the Rhoa Kwi. These Kwi groups migrated with the rising and setting of the sun.
Around the time of the Battle of Yavin, the Galactic Empire hunted the Kwi during their invasion of Dathomir, pushing them to the brink of extinction.
During the Galactic Civil War, Geonosian biological engineers at the Geonosian Bio-Lab situated on Yavin 4 conducted experiments involving mutated Kwis. In 8 ABY, Luke Skywalker and Isolder encountered the Blue Desert People, receiving transportation through the Great Desert of Dathomir before the tribe resumed their simple desert existence. In 23 ABY, Tenel Ka and Luke Skywalker, while aboard the Off Chance, witnessed the Blue Mountain People migrating in the early morning light.
Evidently, the Witches of Dathomir who followed the light side held the Kwi in high regard. The Kwi's willingness to allow someone to ride them was considered a rare and esteemed honor by the Witches.