Elesa

 Elesa (Japanese: カミツレ Kamitsure) is Gym Leader of Nimbasa City's gym of the Unova region. This gym will be the fourth to be challenged by the player. She specializes in -type Pokémon. She will award the player the Bolt Badge if you defeat her. Her first appearance was in Pokémon Black and White. She is also a fashion model besides being a gym leader.

In the games
In the games, after the player exits the Pokémon Musical for the first time, Bianca's father comforts her and tells her to go home with him. However, Elesa steps in and convinces Bianca's father to let her continue her journey. This makes Bianca admire Elesa and makes her want to be a model just like her. She then tells the player she's waiting in the gym for him/her. After defeating her, she goes out to Route 5 and contacts Clay, telling him to bring the Drawbridge down. When it does come down, she wishes the player good luck and returns to the gym.

She next appears along with the rest of the Unova Gym Leaders, with the exception of Cilan, Chili, and Cress, and battle (?) the Seven Sages, allowing the player to continue.

For the rest of the game, she can be found in her gym.

In the Anime
The gang meets Elesa in the Nimbasa Amusement Park. She has a fondness for Electric-type Pokémon, like Ash's Pikachu. She is also a fashion model surrounded by an entourage of her fans. For a supermodel like her she also happens to be wise when she was settling an argument between Bianca and her dad. She not only suggest Ash battle him, but also volunteered to be the judge of their battle. She also has proven to be a tough battler, giving Bianca a run for her money with just her Zebstrika.

Ash was much tougher than Bianca was in his Gym Battle with Elesa, managing to knock out her Zebstrika with his Palpitoad. However, her Emolga was more than a match for him and Snivy, but not Pikachu. Her toughest Pokémon Tynamo was her last hope, but not even it was a match for Pikachu, which gave Ash the win and his fourth badge.

Trivia

 * Her Japanese Leader title is シャイニング　ビューティ. "Shining Beauty"
 * Her design was inspired by Japanese models.
 * She's the first female gym leader who uses Pokémon.
 * She's the second Electric Gym Leader not to use any member of the Pikachu family, Wattson being the first. This is only because Pikachu's family can only be seen later in the game
 * Her name is based on the English name Alyssa and the attribute she uses, Electric.
 * The headphones she wears make her resemble a vocaloid, a computer program that sings songs in a high-pitched, synthesized voice.
 * Elesa also seems to slightly resemble Rin and Len, both of which are vocaloids.
 * She is the only Electric-Type Gym Leader not to wear anything Military related.
 * Regardless of whether the player is male or female, she seems to idolize him/her upon being defeated. This is hinted at two points when she starts using "um" whenever she talks to you and when Clay says that she "has taken a shine to you." (shine is a slang term for idolizing)
 * She may also be related to Volkner hinted by their similar nicknames (shining beauty and shining shocking star) and appearence.
 * Out of the previous female Gym Leaders, Elesa's outfit reveals more of her figure. (Not counting one of Misty's sprites), and she is the only female Gym Leader to have blonde hair.
 * She is one of the few female Gym Leaders to have more male Pokémon than female Pokémon.
 * In the preview, Elesa was seen wearing a sporty outfit.
 * In the episode she debut, Elesa was seen wearing five different outfits. Six if you count her Gym Leader clothes.