Twi'lek is the species name of the humanoid aliens with twin head tentacles. They come from the planet Ryloth, located in a system in the Outer Rim. The Twi'lek language combines verbal components with subtle head-tail movements. With the meanings provided by the head-tail motions, Twi'leks can carry on private conversations in the midst of other species.
Twi'leks are omnivorous. On their homeworld, they cultivate edible molds and fungi, and raise cowlike rycrits for their meat and hides. These beings are nonviolent, preferring to use cunning and slyness instead of force. Twi'leks live in vast city complexes located on their planet's dark side. Each complex is autonomous, governed by a head clan of five Twi'leks who jointly oversee production, trade, and other daily endeavors. These leaders are born into their positions, and they serve until one of their number dies. At this time, the remaining members of the head clan are driven from their complex to die in the Bright Lands of the planet's light side. This makes room for the head clan of the next generation.
As the technology level of Ryloth does not support spacefaring capabilities, the Twi'leks must depend on neighboring systems, such as Tatooine, pirates, smugglers, and merchants for their contact with the rest of the galaxy. They attract these ship with their chief export, ryll. The mineral ryll has legitimate medicinal uses, but it is also a popular and dangerously addictive recreational substance used in the Corporate Sector. One hazard that the Twi'leks face on a regular basis is slavers, who come to their world to fill their ships with Twi'lek slaves.