Alpha and Omega has a few, but the most notable one is Lilly due to her cuteness and situation. She and Garth, another example in regards to his character development and terrible howl gag, are sometimes preferred over Kate and Humphrey, to the point of some fans becoming concerned that they'll disappear in the sequels. (Which they did.)
Anastasia has Sophie, the Dowager Empress's lady-in-waiting who is especially beloved by older male fans for her generous assets.
Marie from Disney's The Aristocats has gotten a huge load of attention from Disney and cat lovers over the years, especially in Japan, she was exclusive to Tokyo Disneyland in the mid 2000's, until she started making appearances in Walt Disney World's Epcot and moved to the Magic Kingdom a few years later. Speaking of Japan, there was a spinoff manga called Miyiya & Marie that was made in 2012 and released in Japan and Brazil where Marie is the main character. The manga later gained a US/Canada release on June 2018 under the "Disney Manga" brand. She's also featured the most in Disney merchandise and anything related to the film. In fact, there was going to be a sequel which starred Marie, but it got cancelled when Disney closed its animation studio.
Lafayette and Napoleon, the two country dogs, are also very popular for how funny they are.
Star from Balto who sadly didn't appear in the sequels is quite well-liked by the Balto fandom. "Circles are a good thing!"
Lumiere from Beauty and the Beast is very memorable, mainly due to his charming personality and performance of Be Our Guest. His voice actor, Jerry Orbach, admitted he was surprised by how popular the character was.
Manolo's cousins, the skeleton bandita looking Adelita twins from The Book of Life, are popular for their design. Though their personalities also help.
The relatively minor character Morkubine Porcupine from Chicken Little has quite a fanbase despite his small screen time and only three lines of dialogue (They were "Yo", "No", and "Whoa"). He's also considered far nicer than most of the characters.
Foxy Loxy also seems to be rather popular, considering how many have complained about her HeelFace Brainwashing.
After the three mains, Bonejangles can be said to be the most popular character in Corpse Bride, and is often the subject of an alternate ship with Emily. Apart from his big song "Remains of the Day," however, Bonejangles is pretty much just an amusing background character in the movie. He never even gets a name on-screen. Being voiced by Danny Elfman helps a lot.
Smiler also seems to be pretty well-liked, if the amount of people (including on this very website) believing that she's the real hero of the movie and supporting her antagonizing of Gene is any indication.
Chernabog and his sequence, Night on Bald Mountain, from Fantasia. Everyone remembers the beautiful pieces of music from the whole thing, but this was the one that stuck to everyone's memory. Everyone that ever watched this was in fear and awe of Chernabog, the sequence is regarded as both so amazing and frightening that it caused the Slavic Satan to haunt many's memories to this day, and it should come as no surprise that, of all the things from Fantasia to put into Kingdom Hearts, they chose Chernabog.
Some of the few other characters who contest him for that popularity are the Shark trio (avertingEverything's Even Worse With Sharks) and the seagulls. All three showed up when Walt Disney World's EPCOT park decided to add the Finding Nemo characters to its The Seas aquarium— the gulls appear in animatronic form outside, Bruce educates kids in a section dedicated just to sharks (despite not having the space for any actual sharks), and Crush hosts "Turtle Time With Crush".
Tad, the fish that says "I'm obnoxious."
The fish with the lisp that shouts "Oh my gosh! Nemo's swimming out to SEA!" has a lot of fans too. In the sequel, she is given more lines.
The anglerfish, for being the biggest source of Nightmare Fuel in the film and being portrayed as a feral, implacable predator, in sharp contrast with the more comedic sharks and seagulls.
The random crab who nearly gets eaten by the seagulls, then proceeds to confuse them with Funny Bruce Lee Noises and karate moves before jumping back into the water.
Pearl the flapjack octopus is very popular in merchandising, despite not having that much screentime.
Mambo from Happily N'Ever After. A cute, purple, awesome, wisecracking, sarcastic cat from a rather mediocre animated movie. Even people who hate the movie love him.
Even those that don't like Home on the Range have singled out Lucky Jack, the cows' jackrabbit sidekick, as being the best character. Reasons generally include his appealing design and Nice Guy personality.
She appears for less than two minutes in the film and has only one line (apart from loudly inhaling), yet still manages to upstage Carol Burnett, Jim Carrey, andSteve Carell. Katie from the CGI Horton Hears a Who! is a perfect example of this trope.
Ruffnut from How to Train Your Dragon, despite having only a few lines and sharing all of her scenes with the other secondary characters. She's aroused by insanity, that's always hot! Being voiced by Kristen Wiig certainly helps.
The original film had the Penguins and King Julien in secondary roles, but lo and behold, they became popular enough to get their own spin-off shows and films.
Madagascar: Escape 2 Africa features a hippo named Moto Moto who has only four minutes of screentime (in an 89-minute-long film), but became the subject of a meme in 2019 because of the catchy song that plays during his scene and him being a funny, if underdeveloped, character.
Captain DuBois is considered one of the more interesting characters to some viewers due to her over-the-top, zany antics and her determination to catch the zoo animals.
Vitaly the tiger is a big one, with his being voiced by Bryan Cranston probably helping. That, and the LGBT community seem to like his muscular appearance.
Tamatoa, the giant crab from Disney's Moana. He only appears in one scene, but his catchy yet creepy Villain Song, "Shiny", makes him quite memorable.
The Princess and the Frog has Charlotte who is utterly beloved despite her supporting role. Not only does she help Tiana achieve her dreams by paying her a lot of money to cater a party, but when an accident happens and Tiana ruins a plate of food, Charlotte accepts it as an accident, takes Tiana upstairs, and gives her some of her own clothes to wear since hers were ruined. She subvert everythingyou'dexpect from a beautiful rich girl. Her energetic and humorous personality also helps.
The first film DVD's 'Technical Goofs' segment gave us Fuzzy Donkey, which alot of fans liked since it's basically Donkey having been transformed into an adorable Donkey-shaped mass of fluff.
Sinbad: Legend of the Seven Seas has Eris who, despite being the villain, has very little screen time. Through Evil Is Sexy and her gorgeous character design, alongside her interesting personality and powers, she is very popular in fandom, to a point that many only watch this movie for her.
The Techno trolls (especially Trollex) have become a subject of interest to the fanbase due to their unique, neon-esque design.
A not-quite-literal example with Hickory, whose good looks, charm, and remorse for his role in Poppy's capture have endeared him to a great number of fans.
In Who Framed Roger Rabbit, the Toon Patrol fanbase makes up an astonishingly high amount of fans, right after Jessica Rabbit then Roger Rabbit. They don't even get named on screen. They don't even survive the movie and they still get the Draco in Leather Pants treatment in fairly equal quantities.
Steve from Wonder Park seems to have a following among animation and comedy fans, with even people who hated the film saying he was one of the best parts.
For those who don't hate them, the Sugar Rush racers are intensely popular, to the point where some think that they deserve their own spin-off series. Particularly Rancis is popular for being the most prominent male racer, fanfiction frequently turns him into Vanellope'sLove Interest.
The Surge Protector, for being a Deadpan Snarker and one of the few characters living in the arcade who isn't a video game character.
The "First Person Shooter", for being a brilliant take on the Featureless Protagonist, as well as also having a personality.