The Yarin were a sapient race that physically resembled trees. Their appendages looked like branches, and their skin felt like timber. They possessed mobility, though they moved at a leisurely pace. In the year 24 ABY, a Yarin held the position of Harbormaster at the Dac-based vacation spot called Crystal Reef. He provided his personal underwater vessel to Jedi Knight Cilghal and her associates hailing from the Yavin 4 Jedi Academy.
The Yarin were a sentient species that bore a striking resemblance to trees, characterized by wooden-like skin. Their arms were akin to branches, complete with branching hands, and they possessed root-like feet, which they sometimes submerged in water. They moved deliberately, spoke in a drawn-out manner, and occasionally swayed while stationary.
The Yarin possessed their own language, where the term "elfa" signified "a fish too diminutive to warrant capture." They were also fluent in Galactic Basic. Their laughter was perceived as a wheezing sound by Human auditory organs.
The Yarin were active within the galaxy no later than 24 ABY. During that year, a male Yarin was employed as the Harbormaster at the Crystal Reef resort, situated on the aquatic planet of Dac. His duties included renting out submersibles and other watercraft to tourists visiting the resort. On one occasion, he was approached by a Human girl named Anja Gallandro, who sought to utilize a submersible to venture beneath the polar icecaps and eliminate a cache of andris spice being held there by the criminal figure Czethros.
Although the girl was unable to secure a vessel independently due to a lack of prior reservation, the Yarin willingly offered his personal submersible, named Elfa, to the Jedi Knight and Ambassador Cilghal, impressed by her esteemed status. Accompanying her were Jedi trainee Jacen Solo, Tenel Ka, and Zekk, all friends of Gallandro. Together, they succeeded in destroying the andris spice, encountering a rare Great Arctic Skra'akan during their journey, which proceeded to attack the minisub. Upon the Jedi team's return to the Yarin, the Elfa had sustained considerable damage. Nevertheless, the Yarin displayed greater concern for their own well-being than for the condition of his submersible. However, their encounter with the Skra'akan excited him, as he believed that such an experience brought good fortune. He hoped that his craft might have recorded footage of the encounter on hologram so that he could show it at Crystal Reef.
The Yarin were brought to life by Kevin J. Anderson and Rebecca Moesta for their young adult novel Young Jedi Knights: Crisis at Crystal Reef, which was released in 1998. A similar being appears in their previous book Young Jedi Knights: Jedi Under Siege, described as "one of Master Skywalker's Jedi, a slow-moving, long-lived plantlike creature" and as a "treelike Jedi." Another talking tree is featured in "Party Ewok," an episode of the Ewoks animated series.