Nini is a recurring character in the Pokémon anime. She is a Pokémon Performer who first appeared in Pathways to Performance Partnering! and one of Serena's rivals.

Nini made her debut appearance in Pathways to Performance Partnering!, where she met Ash and his friends after Chespin and Pancham wandered into her practice area while fighting. She first accused the Pokémon of trying to harm hers but the group cleared it up with her. She mentioned that she planned on entering Pokémon Showcases in which Serena mentioned she'll do the same. Nini asked Serena and the others to judge her performance routine then asked for critiquing when she was done. Serena noted that her Farfetch'd should dance more in sync with Smoochum and Ash noted that Smoochum's Heart Stamp could be flashier. After taking notes, she then asked Serena if she could perform for her for reference.

Once Serena finished her performance, Nini noted that Pancham's dance didn't seem very compatible with Fennekin's dance. However she did notice that the dance was similar to her own Smoochum's dance. So she asked Serena if Pancham and Smoochum could do a dance routine together. Nini was pleased with the results so she asked Serena if she would trade Pancham to her in exchange for one of her Pokémon. Serena declined however.

Shortly after Team Rocket showed up in disguise with Jessie posing as a Pokémon choreographer to take advantage of Nini's situation. She enrolled Nini and Serena's Pokémon, as well as Chespin, into a phony dance class to keep their guard down enough to lure them into a trap. Once the trap was sprung and Team Rocket revealed, Nini demanded her Pokémon be returned to her. However, the team took off in their balloon leaving her and the others to chase them down. Her Pokémon were eventually returned to her some time later after Pancham and Chespin were able to settle their differences and defended everyone from Team Rocket. As the sun was setting, Nini shook hands with Serena before she left the group and told her to get ready for the next Pokémon Showcase.

She reappeared in A Performance Pop Quiz!, where she met up with Serena again and participated in the Anistar City Pokémon Showcase Rookie Class. During the Theme Performance, which consisted of a quiz about Pokémon, she was matched up against Serena and Lily. Her Farfetch'd managed to win the race, allowing Nini to answer the question. However, she answered incorrectly, allowing Serena, whose Pancham came in second, to answer correctly and earn a point. While Nini managed to score a point on a different question, she and Lily eventually lost to Serena and Pancham. Back in the dressing room, Nini congratulated Serena and wished her luck in the Freestyle Performance.

She reappeared in A Dancing Debut! to participate in the Couriway Showcase Rookie Class. After baking a Poké Puff with the help of all three of her Pokémon, she managed to advance to the Freestyle Performance, where she performed her Heartbreak routine. However, it was not enough to impress the crowd, and she ended up losing to Jessilee.

She appeared again in Master Class Is in Session! where she entered the Pokémon Showcase Master Class that was being held in Gloire City. In the first round, she was matched against Concetta and Jessilee. She was doing a good job performing alongside her Smoochum, but Jessilee managed to overshadow her using the smoke from Gourgeist's Shadow Ball. When the results were announced, it was revealed that Nini had gotten fewer votes than Jessilee. As such, she was eliminated from the competition, which made her cry. She was later seen talking to Serena backstage.

(Source: Bulbapedia)