Sylveon, as an Eevee is Azusa's third Pokémon she caught in the episode Azusa's Choice That Makes Eevee Stronger, she evolved into Sylveon in Azusa's Fairy Tale. She has a caring personality despite being a female, she is also Azusa'a first Fairy type Pokémon. She was officially nicknamed Vivian by Azusa.
In "Azusa's First Love!", Vivian was used in a beauty contest earlier by Azusa but she lost, Azusa asks Clemont some advice on what she would do for Vivian's potential to Pokémon Contests. She was used again to fight Team Rocket but lost against Jessie's Wobbuffet using Mirror Coat.
Vivian's known moves are: Moonblast, Hyper Voice, Fairy Wind, Swift, and her ability is Pixilate.