Gigan is the formidable captain of a pirate crew operating in the port town of Awa, first appearing during the narrative arc that introduces the Green Dragon, Jaeha. Her crew is initially presented as a group of pirates, but they are revealed to be fishermen-turned-guardians who work to combat the drug epidemic and human trafficking operations plaguing their town under the corrupt local official, Kumji. Gigan herself is a powerful and respected leader who has established a strict moral code for her crew, forbidding them from killing because she does not want to turn them into murderers.

As a character, Gigan is defined by her pragmatism, strength, and surprisingly maternal nature. She is a tough and untrusting leader who does not accept anyone into her fold without proof of their worth. Her personality is a blend of a hardened warrior and a surprisingly caring mentor. She respects courage and determination above all else, finding amusement and admiration in those who display an indomitable will. Her prominent role in the story is that of a mentor and a temporary surrogate maternal figure for Yona. Yona admits to having no special abilities, and Gigan challenges her to prove herself, testing the young princesss resolve by sending her on a dangerous mission to retrieve a rare medicinal herb called senjuso from a treacherous cliffside. This test is not born of cruelty but of a deep-seated need to see if Yona possesses the inner strength required to survive in their world. Through this trial, Gigan becomes the first strong, non-traditional female role model Yona encounters, showing her that women can be powerful leaders and warriors.

Her relationship with Yona is the most significant of her interactions. Gigan sees a reflection of her own fighting spirit in the princess. In a tender moment, it becomes clear that Gigan would have wanted a daughter with Yona's courage and intelligence, and she treats Yona with a blend of tough love and genuine affection. For Yona, who has no memories of her own mother, Gigan provides crucial emotional support, caring for her without stifling her need to act and grow. Gigan also shares an important dynamic with her crew, including Jaeha, who respects her deeply, and with Yona's companions, earning their trust through their shared struggle against Kumji. She is a peerless ally in combat, easily holding her own in the final battle against Kumji's forces, demonstrating that her reputation as a captain is backed by significant personal martial ability. Through her leadership and her direct involvement in the plan to dismantle the human trafficking ring in Awa, Gigan is instrumental in clearing the path for Yona to take decisive action.