Serena's Sylveon

This Sylveon is a -type Pokémon owned by Serena.

Personality
Sylveon, also as an Eevee, has a huge passion and love for dancing, as she is seen to enjoy dancing her moves on a stage-like rock prior to her capture. She has been described as to be dancing on air by Serena. Eevee is also a very shy Pokémon due to her long time living alone in the forest. Whenever she meets new Pokémon or humans, she would tend to hide behind Serena or her friend, Bunnelby. She is very timid, due her timid nature revealed in A Frolicking Find in the Flowers!. Eevee slowly begins to open up about being around others as shown in Love Strikes! Eevee, Yikes! by letting Bonnie brush her fur. When battling, Eevee uses her dance moves to swiftly dodge her opponents. These dance moves are also used as a Sylveon.

In A Performance Pop Quiz!, Eevee has a fear of fireworks when Jessie as Jessilie performs in the Pokemon Showcase with her Gourgeist which makes her ran away in fright. Her running away due to her fear of fireworks causes Ash and the others to look for her until they have some time to find her which Serena immediately found her after her hiding.

Since evolving, Sylveon is no longer timid and now has full confidence in herself, but she still feels a bit nervous before performing in showcases. She has also began to interact with the other Pokemon, while maintaining her friendship with Bunnelby. With Clemont's Chespin, she was shown receiving encouragement from him and comforting him as a Sylveon when she used to avoid him as an Eevee. With Ash's Pikachu, she showed concern and went to defend him when he was injured in battle as an Eevee. As a Sylveon she was shown cheering for him along with Pancham and Braixen. Lastly, she also interacted with Bonnie's Dedenne, using her feelers to comfort it when bidding farewell.

As Eevee
Sylveon was first seen as an Eevee when it was spotted by Serena's Pancham and Clemont's Dedenne. It was dancing all by itself on a rock near a stream. Serena was impressed by its performing skills and attempts to meet it. However, she discovered that Eevee is very shy among strangers. While she and her friends try to find Eevee, Serena's life was unexpectedly saved when Eevee called out to her to prevent her from falling down a cliff. In gratitude, Serena left a flower crown for Eevee to wear. The next day, Clemont attempted to lure Eevee with Serena's Poké Puffs. However, Eevee took it without Clemont noticing and made him believe that his Chespin ate it. Serena decided to perform in order to get Eevee to reveal itself to the group, which she successfully did. However, Team Rocket interrupted it by trying to capture it. Serena and her Pokémon protected Eevee from them, but Eevee saved them and helped Ash's Pikachu blast Team Rocket off. After that, Eevee joined Serena's team and became her third Pokémon.

Eevee was introduced to Shauna and Tierno. Shauna excitedly told Serena about the Eeveelutions, in which Serena took a liking to Glaceon while Eevee seemed to take a liking to Jolteon. Inside the Pokemon Center, Serena decided that Eevee should get over its shyness, so Ash, Clemont, and Bonnie sent out Pokemon so Eevee could be more comfortable. Encouraged by Clemont's Bunnelby, Eevee brushed her tail over each and every Pokemon except Chespin, whose accidental outburst scared Eevee into tears. Later, Serena and Shauna teamed up against Ash Ketchum and Tierno. Eevee was shy and hesitant to go battle at first, but with the encouragement of the Pokemon and tapping her foot to Tierno's dancing, Eevee was soon able to dance quickly and confuse Blastoise. She then used Swift on Blastoise. Seeing Eevee's dance moves, Serena got inspired. She called off the battle in order to practice them for her performance. Serena was then seen with Eevee, asking her to teach Serena and the team her beautiful dance moves, to which Eevee agrees.

At Anistar City, Eevee was scared of the amount of people at the Pokémon Showcase, so Clemont sent out his Bunnelby to calm her down. However, during the Free Performance, Eevee got scared of Jessie's performance's fireworks. Serena screamed for Eevee and desperately searched for her, but to no avail. Eevee, who was hiding under a bench, gathered all her strength to run to her trainer. Seeing that Eevee was safe, Serena delivered her performance, in which Braixen and Pancham utilized Eevee's dance moves. Eevee was dazzled after seeing the performance, sparking her interest at Showcases.

Eevee caught the interest of a wild Quilladin. She didn't love the Quilladin, and frequently used Protect and Double Team to get away from its acts of love. However, Eevee was soon drawn away by a lure along with Bunnelby, Dedenne, and Squishy by Team Rocket. Though thanks to Bunnelby, Eevee was soon reunited with her trainer. Quilladin, falling in love with a Flareon, bid Eevee farewell and ran to chase Flareon after Eevee rejected Quilladin's love one last time.

Eevee participated in her first Showcase at Couriway Town. Though nervous at first, she was quickly calmed down by Serena and her team which is both Pancham and Braixen. During the Theme Performance, Eevee was excited and happy that Serena and Pancham won. During the Free Performance, Eevee, Serena, and Braixen were able to charm the audience with their dance routine. While Eevee was dancing with Serena, she leapt into the air and landed on Braixen's branch. However, she got distracted by the crowd and fell off. Eevee felt upset, but Serena encouraged Eevee to keep on dancing and sticking to the routine. Because of the mishap, Serena didn't win. Later, Eevee felt bad because she blamed herself for the loss, but Serena told Eevee not to worry, and she raised Eevee up into the air, their bond growing closer.

Eevee was seen playing around with the other Pokemon in the flowerfields as Ash and the group are having a tea break. When Ash's Noibat screams due to being attacked and poisoned by the wild Breloom. Eevee and others are recalled back by Ash and the group.

Eevee is first being brushed by Serena as both Braixen and Pancham are arguing about who's next to be brush as Serena scolds them. After brushing, Serena and her friends were invited to a dance party hosted by Monsieur Pierre and the current Kalos Queen, Aria. Although Eevee wasn't sure about attending the party, but accepted the invitation when she partnered with Bunnelby. At the party, Eevee had a wonderful time dancing with Bunnelby and she happily danced with a trainer's Furret when everyone switched partners. After the dance, Ash and Serena were chosen to participate in a tag battle against James and Miette. Eevee partnered up with Ash's Pikachu and battled against Miette's Slurpuff and James' Inkay. During the battle, Eevee was severely damaged. However, when Serena gave Eevee some encouragement, she awakens as it forms a long single ribbon that sticks on Eevee's fur to cover Serena's hand and surprisingly evolved into Sylveon. Sylveon manages to deflect Slurpuff's Energy Ball with her newly learned Fairy Wind despite Serena tells her to dodge, thus helping Ash and Serena win the battle in the process by defeating both Inkay and Slurpuff with Fairy Wind. Clemont also tells Serena that Sylveon is one of the Eeveelutions much to her surprise.

Sylveon was seen being brushed by Serena when Sawyer tries to ask Ash about Greninja's special form known as Ash-Greninja form which Ash was still unaware of its special ability.

As Sylveon
Sylveon lost a bit of confidence when she recalled the memory of losing her first performance with her friends as an Eevee before performing in the Fleurrh City Showcase. Luckily, her confident was restored again after Serena encouraged her by giving her a Poké Puff. Better than that, they won the Showcase. Nonetheless, she became worried when Palermo told them something serious.

Sylveon, along with Serena's other two Pokemon, arrived at Gloire City to participate in the Master Class Tournament. Serena dressed up Sylveon in her performance costume while backstage. When Serena and her Braixen performed and won the first round, Sylveon cheered along with Pancham. In the second round, Serena used Sylveon and Pancham. They were also able to advance to the semi-finals along with Jessie and Shauna.

Serena, using her Sylveon and other Pokémon, were able to defeat Shauna and Jessie and challenge Aria for the title of Kalos Queen. During her performance, Sylveon used Fairy Wind and Swift to charm the audience. However, when Serena touches the floor and spraining her left hand to make her fall, Sylveon uses her ribbons to strap her down to make her flip to end the performance. Despite having performed beautifully, Serena still lost to Aria. Palmero later gave Serena a card, telling her that she was willing to train Serena. Serena declined, wishing to finish her journey with Ash. Sylveon approved of her trainer's choice by smiling and waving her feelers, as she knew that she could continue to stay with her friend Bunnelby.

When Team Flare began their assault on the Kalos region, Sylveon battled several Team Flare Grunts and their pack of Houndoom in order to buy some time for Mairin to retrieve Chespie from the Lysandre Labs.

However, the rescue mission was interrupted when Lysandre, the treacherous leader of Team Flare, activated the Megalith, absorbed Chespie, and formed into a destructive version of a Zygarde. The Megalith Zygarde started heading towards the Anistar City Sundial, which it intended on fusing with it so it will create an explosion that would destroy the planet and wipe off nearly every living being. While Ash and Alain rescue Chespie, Sylveon protects Serena, Bonnie, and Mairin from the attacking roots of the Megalith Zygarde and after Chespie was successfully retrieved, Sylveon joins in the final battle against Team Flare.

After Team Flare's evil ambitions were finally put to an end, Sylveon, along with the rest of Serena's Pokémon, received Honor of Kalos medals for their heroic efforts against Team Flare.

In the end of XYZ, Sylveon bidded farewell to Bunnelby with teary eyes and comforted Chespin with her feelers. Then, along with Serena, Braixen and Pancham, they began their new journey in Hoenn.

Voice actresses

 * Mika Kanai (Japanese as Sylveon and English as Eevee)
 * Erica Schroeder (English as Sylveon)

Trivia

 * Serena's Sylveon, as Eevee, was the second Eevee to be caught by a traveling companion of Ash's; the first one being May's Glaceon.
 * Along with Serena's other two Pokémon, Sylveon enjoys a certain aspect of Pokémon Performing. In Sylveon's case, it's dancing.
 * Sylveon is the first Eeveelution that belonged to a main character to evolve onscreen.
 * Among Serena's team, Sylveon is the only one without an item.
 * Braixen has her branch while Pancham has his sunglasses.