The nek was a predatory species native to the galaxy, lacking sentience. These creatures were characterized by their stocky build, yellow fur, piercing teeth, and a rough, barking vocalization. Neks were capable of achieving impressive speeds when running, leading humans to consider them a threat. Despite their aggressive nature, neks could be trained. On the planet of Lothal, an orchard was guarded by neks under the command of a nek owner, who used whistles to direct his animals. Approximately around 6 BBY, Imperial cadets Zare Leonis, Beck Ollet, and Merei Spanjaf were attacked by these creatures while visiting the orchard, but the guard subsequently recalled the neks.
Not long before the Battle of Yavin in 0 BBY, Rebel pilots Col Takbright and Luke Skywalker engaged in a short conversation. Pilot John D. Branon repeatedly pressed Takbright to reveal what Skywalker had said, prompting Takbright to mentally liken Branon to a nek fixated on a bone. Around 4 ABY, in the early months following the Battle of Endor, Sinjir Rath Velus, a former Imperial, found himself followed by a Twi'lek named Orgadomo Dokura. Velus then compared Dokura to a lost nek.
In Star Wars canon, the first appearance of neks occurred in the junior novel Servants of the Empire: Edge of the Galaxy. This book was authored by Jason Fry, published under the Disney–Lucasfilm Press banner, and released to the public on October 21, 2014. Within Star Wars Legends continuity, neks initially appeared in the 1991 comic book Dark Empire 1, which was written by Tom Veitch and featured illustrations by Cam Kennedy.