"Her father is a fisher, and her mother works in the marketplace. Perhaps because of her parents, she grew up playing with Water-type Pokémon and eventually made it all the way to being a Gym Leader. She met Sonia during their Gym Challenge, and they continue to be close friends. Nessa often gives Sonia fresh seafood from Hulbury. She has declared that Milo of Turffield is her rival, but Milo responded by saying that his rival is himself."
Rare League Card
"Nessa is incredibly popular, both as a Gym Leader and as a model. Many people even think the Gym Leader Nessa and the model Nessa are two different people, since she shows a completely different attitude in each role. She had the misfortune of being defeated in the first match of the Finals, and those who knew of her indomitable nature worried that this would impact her work as a model. Despite her loss, she was still able to give her fans a perfect smile. Things were not nearly as peaceful with her Gym, however... "
Nessa made a cameo appearance in Letter. She reappeared in another cameo in Buddy, where she was seen in the water alongside a Qwilfish.
Nessa appeared more prominently in Early-Evening Waves, where she suffered a defeat in the Champion Cup at the hands of Milo. Afterwards, she was approached by Chairman Rose, who implied the loss happened because she was distracted by her simultaneous modeling career. This agitated her, and she vented her frustrations to Sonia. Later, during a photo shoot, Nessa was reunited with a Feebas she had met as a child, which was now a Milotic. Afterwards, she decided to disregard Rose's words and continue being both a Gym Leader and a model.
During the time she had been defeated in battle, Nessa felt very concerned about juggling between her dual careers as a Gym Leader and a model. This increased greatly with Chairman Rose's implication that her modeling career was distracting her. She also has a great friendship with Sonia.
As a child, Nessa encountered a Feebas, and encouraged it to grow bigger. She also requested if she could ride on it once it evolved. Years later, Feebas returned as a Milotic, who fulfilled the request from earlier and let Nessa ride on it. This encounter prompted her to move forward with her goal to be both a Gym Leader and a model at the same time.