Nat Secura was a male Twi'lek (his gender was male) and also the cousin of the Jedi Knight, Aayla Secura. His father was Lon Secura. He held the position of Secura heir.
In the year 30 BBY, Secura was abducted by a pair of Morgukai who were working for Kh'aris Fenn. He was imprisoned in Kh'aris' fortress dungeon alongside Jedi Master Tholme. Tholme attempted to free the young Twi'lek. As the torture droid AX/RX received orders to terminate both captives, Tholme launched an attack on the droid. Subsequently, another Jedi, Aayla Secura, entered the prison cell and severed the droid's head. He successfully fled the fortress with Tholme, while Aayla aided her master, Quinlan Vos, in overcoming the two Nikto Morgukai.
When Bib Fortuna made his return to Ryloth seeking vengeance on his people, Secura suffered severe scarring, particularly affecting his lekku, which rendered him unable to speak in Twi'leki. His mother rebuked Bib, leading to her execution at his hands. Following this, Bib treated him and removed him from Ryloth.
Later in his life, Bib Fortuna kept Secura within Jabba's Palace. Jabba harbored a strong dislike for Nat and subjected him to harsh treatment, ultimately deciding to end his life. In an attempt to "save" Secura from the rancor, Fortuna arranged for the B'omarr Monks to extract Secura's brain. Secura's now-lifeless body became food for the Rancor, while his brain was securely housed within a B'omarr monk spider walker.
Secura soon experienced the onset of mental instability, unprepared to cope with his new and horrifying situation. The monks cautioned Fortuna that if he failed to locate a new host body for Secura promptly, he risked succumbing to madness and death. Fortuna intended to find cloners to clone a new body for Secura. Until that time, Secura desired to inhabit the carbon-frozen form of Han Solo, leading his friend to devise a plan to steal the body right from under Jabba Desilijic Tiure's watchful eye. However, the scheme went awry when Solo and his companions managed to escape Jabba's grasp. Secura remained within his brain walker, accompanied by several new "initiates" to the B'omarr Monks, including Fortuna. He assisted Fortuna in adapting to his brain walker, and eventually, they both made their escape from the palace.
After Jedi Secura rescued Tholme and Secura, Tholme introduces the little Secura to his Padawan. However, he mistakenly refers to the boy as Lon, which is actually the name of his father, rather than Nat.