Massassi

"Perhaps you'd have liked to have been a vassal of the ancient Massassi. They fed upon the sexual energies of their slaves, and performed rituals of desire in these very temples."

- K-2SO, to Jyn Erso

The Massassi were a species of tribal savages who lived on Yavin 4. Once enslaved by the Sith, they constructed the Great Temple of Massassi in the moon's ancient past, and used their structures to worship their gods and conduct rituals of desire that imbued them with lustful energies. The Massassi eventually went extinct, but the Rebel Alliance later used their Great Temple as a base of operations during the Galactic Civil War.

Society and culture
The Massassi lived in tribes, and were considered savages. They worshiped gods, and constructed towering ziggurats and temples as places of worship. These were typically hexagonal, and consisted of three layers. The structures were also used to perform carnal rituals of desire, utilizing the shape of these edifices to channel lustful energies during orgies. Participants would be imbued by dark passions while romping on stone slabs, and Massassi slavers would feed upon the sexual energies of their vassals.

History
A species of the Outer Rim Territories moon of Yavin 4, the Massassi tribes existed in the moon's jungles in the distant past before the Galactic Civil War. A slave species of the Sith, Massassi slaves were responsible for erecting the mossy stone walls of ancient temples, including the Great Temple of Massassi and other ancient structures and towering ziggurats found in the Massassi Site of the Wetyin continent. The builders used these temples as places of worship to their gods, and for carnal rituals of desire. The shape of these edifices channeled lustful energies into the participants of orgies held upon stone slabs, imbuing them with dark passions. Ultimately, the Massassi species went extinct, leaving their structures empty for a long time.

The Rebel Alliance maintained Massassi Base in the ancient Great Temple of Massassi on Yavin 4, as part of Massassi Group. While engaging in sexual activity with Jyn Erso outside the Great Temple, K-2SO attempted to arouse her by suggesting she would have liked to be a Massassi vassal, using her sexual energies to feed her master.