The Codru-Ji were a humanoid race, possessing four arms, who resided on the planet of Munto Codru. They began life as six-legged canine creatures called Wyrwulves. At the onset of puberty, they would enclose themselves in a cocoon, emerging several weeks later as a two-meter-tall adult humanoid. The Codru-Ji slept in a standing position and used hypersonic frequencies for communication.
Due to the limited number of significant exports from their homeworld, the Codru-Ji managed to maintain their isolation from the affairs of both the Galactic Empire and the New Republic. This enabled them to focus on their intricate and complex internal political system. Prominent Codru-Ji families were frequently subjected to "coup abductions," which were ritualistic kidnappings of children carried out by their political adversaries. These abductions almost invariably concluded with the payment of ransoms and the safe return of the abducted children.
Elaborate stone castles were dotted across the landscape of Munto Codru. These structures were not built by the Codru-Ji themselves, but rather by an unidentified, long-extinct civilization. Many Codru-Ji avoided these castles, believing them to be haunted. Nevertheless, they were occasionally utilized as provincial capitals.
In the year 137 ABY, the inhabitants of Munto Codru were compelled to unite their tribes under the authority of the Empire, which was controlled by Darth Krayt of the One Sith. A Sith Lord by the name of Darth Kruhl personally traveled to the planet in order to force the Codru-Ji leaders to accept Imperial dominion and to eliminate any figures who opposed it.
The Codru-Ji possessed a unique two-stage life cycle that distinctly separated adults from their adolescent stage. Codru-Ji offspring were born as meter-long canid creatures, exhibiting the six limbs that were characteristic of all Codru-Ji. These young ones, known as Wyrwulves, were often mistaken by outsiders as mere family pets, a perception reinforced by their inability to communicate beyond snarls and growls. These juvenile creatures were sociable, often licking guests as a form of greeting; however, they were also capable of delivering a powerful bite to ward off attackers. Wyrwulves were given affectionate nicknames, such as "Hrika" or "Lirri," and did not receive their formal names until they reached adulthood. Wyrwulves matured for a period of eight years before entering a cocoon. They remained within this rubbery blue cocoon for a span of several weeks before emerging in their adult form.
Adult Codru-Ji presented as humanoids, distinguished by their possession of four arms. They shed the dense fur of their earlier form, but retained other features such as their resilient skin. Codru-Ji hearing extended into the supersonic range, undetectable to many other species. The average height of a mature Codru-Ji was 1.6 meters. Among their four limbs, Codru-Ji possessed one dominant hand, with which they exhibited the greatest skill. The remaining limbs served as "off hands," though they were still functional. A peculiar characteristic of the Codru-Ji was their habit of sleeping in an upright position. They developed sleeping harnesses to secure adults in this posture. Adults could rapidly acquire skills using a single hand, and then replicate that ability across all of their limbs. They could endure days without sustenance or water and possessed heightened senses that allowed them to scan their surroundings effectively.
Some scientists hypothesized that the Codru-Ji were descendants of a highly advanced, yet extinct, species that had left behind numerous ruins on Munto Codru.
The Codru-Ji were notably xenophobic, exhibiting reluctance to grant members of other species access to their society. While not particularly fearful of off-worlders, the Codru-Ji were concerned about the potential for outside influences to negatively impact their culture. Certain aspects of their culture, such as the ritualistic kidnapping of children of political rivals, were considered barbaric by galactic standards, leading the Codru-Ji to believe that it was best to remain detached from the broader galactic stage.
The Codru-Ji were conceived by Vonda N. McIntyre for her novel The Crystal Star, which was published in 1994 by Bantam Spectra. Following that initial appearance, their backstory was further developed in reference works such as The Essential Guide to Alien Species, The Essential Guide to Planets and Moons, and the Ultimate Alien Anthology. After making several cameo and background appearances in subsequent novels, the Codru-Ji once again played a significant role in the Dark Horse comic Legacy (2006) 13, which was published in 2007.