Drell are an omnivorous amphibious humanoid race with bright neon coloring and black markings. Their muscle tissue is slightly denser then humans, giving them a wiry strength. They appear to have five fingers on each hand, albeit the ring and middle fingers are fused. Females have breastlike protrusions, and their head "frills" are more pronounced than males. Drell have two sets of eyelids; the inner lid is milky-white and closes from the left and right, while the outer lid is black and closes from top and bottom. Drell possess the ability to shed tears. Their skin is infused with a venom mild enough to be served in drinks, and may cause mild hallucinations if ingested.
They have an average lifespan of 85 galactic standard years and possess eidetic memory, an adaptation to a world where they must remember the location of every necessary resource such as vegetation, drinkable water or prey migration paths across vast distances. The memories are so strong that an external stimulus can trigger a powerful memory recall. These recalls are so vivid and detailed that some drell may mistake it for reality.
They were rescued from their dying homeworld by the hanar following the first contact between the two. The Drell are grateful to the Hanar for saving some of their race, even if few (375,000 saved out of billions), and have remained loyal to the hanar for their camaraderie. The drell came from arid rocky deserts, so the hanar homeworld of Kahje which is humid and ocean-covered proved tolerable only when the drell stayed inside a climate-controlled dome city. Because of this Kepral's Syndrome, caused by cumulative long-term exposure to a humid climate is the leading cause of death for drell on Kahje. This syndrome for which there is currently no known cure erodes the ability of the lungs to take in oxygen, and eventually spreads out to other organs. Leading hanar scientific authorities are working on creating a genetic adaptation.
The debt of gratitude that the drell owe the hanar is referred to as the Compact, which the drell fulfill by taking on tasks that the hanar find difficult, such as combat. Any drell may refuse to serve, but as being requested to serve is a great honor, few turn down the offer. Some drell grow a close personal relationship with the hanar enough that they will learn the hanar's "Soul Name". Drell sometimes get implants in their eyes to allow them to observe the bioluminescence the hanar use for communication. This allows them to see ultraviolet light as a silver color, but might lose differentiation between colors at the opposite end of the spectrum, such as the difference between dark red and black.
Most drell are deeply religious, believing that they have souls separate from their bodies. They also believe that their body can be directed as a separate entity from themselves and therefore take no responsibility for the actions of the 'body'. The drell religion is also polytheistic, with the drell having multiple gods whom they pray to in varying situations. This religion include at least three gods: Amonkira, Lord of Hunters; Arashu, Goddess of Motherhood and Protection; and Kalahira, Goddess of Oceans and Afterlife. Many of the older traditions of the drell have begun to die out. The younger generations no longer believe the old ways of their ancestors can help them now, with so many other ways to interpret one's place in the universe. Many drell have embraced the hanar Enkindlers or the asari philosophies.