Kortanio was a Kessurian member of the Path of the Open Hand cult who ventured out into the Galactic Frontier in service to the Path and was not present when the cult met its violent end on its home planet Dalna in 382 BBY. At some point between the Path's dissolution and around 381 BBY, Kortanio and their partner Esstrop were among the few Path members tracked down by the pirate leader and former Path member Marda Ro and joined her group. After they joined the group, Ro showed them a creature called the Great Leveler.
Kortanio served Ro as a pirate alongside Esstrop, the human Milan Stor, and the Twi'lek Fori Nagor. At some point no earlier than 379 BBY, they undertook a raid on a refugee camp. Nagor presented refugees captured by the raiders during the attack to Ro in the Gazes throne hall, but Ro ordered her to set them free. Kortanio and Esstrop later escorted the Evereni twins Vika and Velya Faer to the throne hall for a meeting with Ro. At some point, Ro mentioned Kortanio in a recording she made for her descendants, which her great-great-grandson Marchion Ro had listened to by 252 BBY
Kortanio was a Kessurian who became a member of the Path of the Open Hand cult at some point no later than 382 BBY. During their time in the Path, they traveled the Galactic Frontier in an exploratory shuttle to preach the Path's teachings alongside their partner Esstrop. As a result, they were not present on the Path's home planet Dalna during a battle in 382 BBY that led to the Path's end and were unaware of it.
At some point between the battle and around 381 BBY, they were tracked down by the Evereni Marda Ro—a former member of the Path—who searched for the few scattered Path members that were left. She told Kortanio a false story about how the Path ended to put herself at the center of their faith and desires and told them to either join her group of pirates or stop with any Path activity. Kortanio and Esstrop were among the few that chose to join Ro.
After Kortanio joined Ro, she took them to her ship, the Gaze Electric, where she showed them a creature that consumes the Living Force called the Great Leveler. Ro explained that the group's purpose was to be caretakers of the beast, so that one day it could consume those who abuse the Force. She also added that the group Kortanio had joined had no shared religion or a story to tell the galaxy and all they need to do was survive.
Kortanio and Esstrop became quickly faithful to Ro and became her best raiders. The two would move in their shuttle to take things that they would then bring back to the Gaze Electric to present to Ro. Kortanio and their partner would sometimes work together with their fellow raiders Milan Stor and Fori Nagor to conduct bigger raids.
They carried out one such attach at some point no earlier than 379 BBY, when they raided a refugee camp and—as the refugees lacked posesssions to steal—kidnapped the refugees instead. Back on the Gaze, Nagor presented the refugees to Ro, who was enraged at their actions. Ro ordered Nagor to let the refugees go, with the exception of a Force-sensitive green-skinned man who Ro took to the Great Leveler. Later, Kortanio and Esstrop escorted the Evereni twins Vika and Velya Faer to the throne hall of the Gaze Electric after the Faers accepted an invitation from Ro to meet with her.
Later, Ro talked about Kortanio in a message she recorded for her descendants and stressed the important of passing on their name. By 252 BBY, during his youth, Ro's great-great-grandson Marchion Ro had listened to her journal, including the entries where Kortanio was mentioned.
Kortanio was in a relationship with Esstrop, a fellow Kessurian. They could not stand being stuck in one place and Ro regarded them as a great seeker. They turned their faith over to Ro quickly and were one of her best raiders.
Kortanio and Esstrop had a shuttle they used for transport while serving the Path and later Ro.
Kortanio appeared in a flashback in the short story "A Closed Fist Has No Claws," written by Tessa Gratton and published in the 2023 young-adult anthology The High Republic: Tales of Light and Life as a part of the Star Wars: The High Republic multimedia project.