Yūka is a character of the day who appeared in Ep 140.
Her father, Nagai, is the owner of a toy store that sells figurines of the town's favorite superhero, Gligarman. Satoshi and his friends later realized Nagai himself was Gligarman, who donned a purple costume to fight crime and—perhaps more importantly—to boost sales in his shop. After he became too old to effectively carry out his duties, Yūka took over the role, under the moniker of Gligirl.

A young boy named Satoshi embarks on a journey to become a "Pokémon Master" with his first Pokémon, Pikachu. Joining him on his travels are Takeshi, a girl-obsessed Rock Pokemon Trainer, and Kasumi, a tomboyish Water Pokémon Trainer who may have a crush on him. Satoshi and Co. end up traveling through various regions, including Kanto, the Orange Islands, and Johto, and then enter the Pokémon League competitions there. Along the way, they run into many confrontations with Musashi, Kojirou, and Nyarth, a trio of Pokémon thieves who are apart of an evil organization called "Team Rocket". But everytime Team Rocket try to do their evil deeds, they fail thanks to Satoshi and his Pokémon.<br><br>
(Source: Anime News Network)

Mariana Ortiz is a Mexican voice actress.

Yuuka