A male Etti who hailed from the planet Etti IV, Seyyerin Itoklo was sensitive to the Force and underwent training to become a Jedi within Luke Skywalker's New Jedi Order. In the year 25 ABY, the galaxy found itself under invasion by the Yuuzhan Vong, beings from beyond the galactic rim, who considered Skywalker's Jedi Order a significant obstacle to their aims of galactic domination. By this period, Itoklo had achieved the status of Jedi Knight. However, early in the war's second year, the Etti was handed over to the invading forces and subsequently met his end, a consequence of a Yuuzhan Vong ultimatum that demanded the Jedi Order's surrender in exchange for halting their invasion.
Seyyerin Itoklo, originating from the planet Etti IV, belonged to the Etti race, a Near-Human species characterized by their fair skin and graceful, slender builds. Being attuned to the Force, Itoklo received instruction as a Jedi under the tutelage of Master Luke Skywalker within his New Jedi Order. Nevertheless, in the year 25 ABY, the galaxy faced an invasion from a species of warriors originating from beyond the galaxy, known as the Yuuzhan Vong. As they aggressively moved from the Outer Rim Territories towards the Galactic Core, certain leaders within the Yuuzhan Vong perceived the New Jedi Order and its members as a threat, viewing them as the galaxy's most formidable combatants. By the second year of the Yuuzhan Vong War, Itoklo had attained the rank of Jedi Knight.
Following the capture of the Core World of Duro, Warmaster Tsavong Lah of the Yuuzhan Vong issued a demand to the galaxy's inhabitants, urging them to surrender all members of the New Jedi Order to him in return for halting the Yuuzhan Vong's advance. In the wake of this ultimatum, numerous Jedi were swiftly killed, either by the Yuuzhan Vong themselves, by collaborators within the Peace Brigade, or by ordinary citizens who believed the invaders' promises. Itoklo was among the early victims of this purge; the Etti Jedi Knight was handed over to the Yuuzhan Vong in compliance with Tsavong Lah's decree and subsequently killed. Kyp Durron, a Jedi Master who advocated for a more aggressive approach in combating the Yuuzhan Vong, later criticized Skywalker during a Jedi gathering on the planet Coruscant, attributing the deaths of Itoklo and other Jedi to Skywalker's defensive strategies.
The character of Seyyerin Itoklo has never been directly depicted in any Star Wars media; his name only appears in Greg Keyes' novel The New Jedi Order: Edge of Victory I: Conquest, which was released in April of 2001. While two of the three Jedi Knights mentioned by Kyp Durron during his criticism of Skywalker were briefly shown in the novel's prologue as they were killed, Itoklo's death was only mentioned, and no details regarding his age, gender, rank, or species were provided.
In Daniel Wallace's Who's Who in the New Jedi Order, an article featured in Star Wars Insider 57 almost a year later, additional information about Itoklo was revealed, identifying him as a male Etti Jedi Knight. Itoklo's entry also stated that he "suffered the consequences" of Tsavong Lah's order that all Jedi be surrendered to the Yuuzhan Vong, implying that Itoklo was captured and killed by the invaders. Who's Who in the New Jedi Order featured illustrations by Dan Veesenmeyer and Russell Walks, including a drawing of Itoklo.