Ryloth is a planet located in the Outer Rim, home to the Twi'lek people. The world is divided into two polar opposites: the Bright Lands, where the heat is extreme and desert is the dominant landscape; while the other side is forever frozen and dark.
The only stable location on the planet is the mountain ridge between these two sides, known as the "Life Zone". Here the Twi'lek people built their cities inside caverns. The capital city, Kala'uun, is home to the largest concentration of sentients, drawing in tourists.
When the drug Ryll was first discovered on the planet, Twi'lek society was forced to center itself around trading in the black market. Many Twi'lek females are sold into slavery as dancers, while the males go on to serve criminal underlords.