A skilled mercenary, his only goal seems to be acquiring a desired amount of pay per contract, as he appears distraught after being told by the Elf King that he will only receive half of the payment until his duty has been fulfilled. Despite this, he is headstrong and willingly duels against stonekeepers, including Emily and Trellis.
In "The Cloud Searchers", the Elf king hires Gabilan as an assassin to hunt down Emily Hayes and her companions, along with the Elf King's son, Trellis, who has betrayed him again. Though he questions the Elf King's motives for wanting to kill his own son, the only thing he seems to care for is his payment. When he is told he will only be given half until his mission has been completed, he is upset. Gabilan questioned the elf servant, Logi, if he appreciated working for the Elf King, to which Logi explained that he is simply acting out of survival. Gabilan proclaimed that Logi would be given a better wage "when [he] is king", right before riding off.
Somewhere along the line, Gabilan had come across Luger, who had been defeated by Emily, Navin, and the gang at Demon's Head Mountain. He used his memory-erasing gun to wipe out Luger's memory.
Gabilan managed to locate Emily by interrogating two elf soldiers at a bar by threatening to erase their memory. He utilized the device on one of the soldiers after they refused to tell him and then viewed the information through a screen. The waitor told Gabilan that the two men on-screen were Emily's pilots and that they would be taking her to the floating city of Cielis.
Luger pursued the airship much later and eventually gained access when the ship stopped at a refueling station. When they reached a floating island near Cielis, Gabilan revealed himself and threatened to kill Emily's mother. Emily and Trellis fought against him in a floating palace, where he eventually fell and landed safely onto his eagle.