Opalescence

Opalescence, or Opal for short, is Rarity's cat. She is introduced in the episode Suited for Success.

Character design and personality
Opalescence looks like a typical Persian cat, with white fluffy fur, a wide face, and shortened muzzle. She wears an opal-studded collar around her neck, and a purple ribbon on the top of her head. She is irritable and often yowls and hisses in anger at her owner, Rarity, and other ponies.

Suited for Success
Opalescence first appears in the opening shot of Suited for Success. Rarity has a "conversation" with her as one would with a pet, thanking her for her assistance and asking for her advice, while Opal seems bothered and annoyed by being given things to carry and being carelessly flung off the fabric that she was sitting on. Rarity confides in Opal throughout the episode, but Opal only hisses and mews in return. When Rarity locks herself in her room after her failed fashion show, her friends strand Opal in a tree to lure Rarity out of the room; Opal doesn't look pleased at all from the situation.

Other appearances
Other than Suited For Success, Opal is featured briefly in Stare Master, Owl's Well That Ends Well, The Best Night Ever, Sisterhooves Social, May the Best Pet Win!, and Sweet and Elite. She swipes and chops off a lock of at Sweetie Belle's mane and offers a smug look, after Sweetie Belle suggests that her special talent might be caring for animals, in the episode Stare Master. Opal is briefly seen when Spike takes a stuffed toy mouse from her in Owl's Well That Ends Well, which he uses as a ketchup-bloodied carcass in his attempt to frame Owlowiscious for its killing.

Opal is pitted by Rainbow Dash against some prospective pets as a test of "guts" in May the Best Pet Win!. The animals quake in fear when Dash dares them to take away Opal's favorite toy, a stuffed mouse. One of the contestants, a butterfly, successfully mesmerizes Opal and whisks away her toy. Tank, the tortoise, tries to trap Opal in her carrying case by flipping it over her, but she gets out of the way in time and fiercely scratches at his shell. Near the end of the episode, Tank does succeed in taking away the toy from Opal while she is busy scratching his shell.

Opal accompanies Rarity to Canterlot during her stay at Canterlot Castle in Sweet and Elite. Opal indulges in much of the royal city's many regal splendors with Rarity, and when Rarity decides to create a new dress as a gift for Twilight's birthday party, Opal tries to keep her focused on her work (As Rarity was also trying to get in with Canterlot's sophisticated crowd at the same time). Ultimately however, the two stay in Canterlot longer as Twilight and the others unexpectedly show up to host the party there since Rarity lied that she had to stay to take care of a "sick" Opal. She ended up soaking Opal in water to maintain her cover, as she tried to attend both Twilight's party and a sophisticated social next door. Fluttershy gave Opal her usual tender love and care, hoping to make her "better".

Gallery

 * Opalescence image gallery

Trivia

 * Whenever Opal is focused on throughout the show, her actions are accompanied by a brief harpsichord trill.

Opalescence