Many unforgettable characters came out of the Pokémon anime. Misty, Brock, Dawn, Serena, and of course, Ash are some of the most recognizable and fan-favorite ones, although many have come and gone over the show's history. Even now, the anime keeps delivering exciting and entertaining adventures twenty-four years after it premiered.
The Sun & Moon season, which focuses on Ash's time in the Alola region, is a turning point in the franchise. It featured a visible change in the animation style and featured landmark events in Ash's journey, mainly him finally becoming the Champion of a Pokémon League. And he does so accompanied by a cast of colorful and memorable characters that remain popular within the fan community.
Gladion
Like most of the anime's most memorable rivals - Gary, Paul, Tobias - Gladion has more of an antagonistic attitude towards Ash. He's a brooding and impatient boy who harbors deep regrets for being unable to protect his little sister, Lillie, from an Ultra Beast's attack. He enjoys the company of his Pokémon more than any human's and proves to be a skilled and promising Trainer.
Gladion shares an entertaining rivalry with Ash. They don't necessarily like, but they respect each other and share unforgettable battles throughout the season.
Bewear
Some Pokémon become breakout stars of the anime because of their distinctive personalities and meaningful role in the plot. Bewear is one of such, serving as comedic relief for most of the season. Friendly and caring, Bewear takes a particular liking to Team Rocket. The Pokémon goes to great lengths to protect the trio, even going all the way to Kanto to ensure their safety.
Bewear's obsession with Team Rocket is also detrimental for the trio at times. Once, it "rescued" them before they could finally defeat Ash and capture his Pikachu.
Hau
Much like his game counterpart, Hau is an overly enthusiastic young Trainer. He serves as Ash's friendly rival and has a sunny disposition that stands in stark contrast to Gladion's antagonistic nature.
Unlike the games, where he proves to be a promising but inexperienced Trainer, Hau is much less competent in the anime. He does earn a lot of experience throughout the show, but it still isn't enough to make him a true standout. Hau plays a less prominent role in the anime, being only a recurring character.
Lana
Out of all of Ash's classmates in Alola, Lana is the quietest one. She's a shy, gentle, and kind young girl who loves Water-type Pokémon, surfing, fishing, and spends most of her time with her Pokémon. She's also courageous and the bravest out of all of Ash's friends.
After visiting Kanto, Lana becomes close friends with the anime's other Water-type enthusiast, Misty. The two exchange letters and Lana even invites her and Brock to visit Alola. It's clear that Lana sees Misty as both a friend and a role model.
Sophocles
Sophocles is one of the anime's most intelligent characters. He's an inventor who loves Electric-type Pokémon and uses them to power his many creations. He's so passionate about his work that he often alienates himself from others, preferring the company of his Pokémon and machines.
Much like Clemont before him, Sophocles is at times the butt of the joke, mainly because of his lack of athletic skills. He's also afraid of the dark but keeps his Togedemaru outside of its PokéBall at all times.
Rowlet
Rowlet is Sun & Moon's second memorable Pokémon character. It's Ash's first Pokémon in Alola and effectively acts as his Starter. Like some of Ash's previous Pokémon - Charizard, Bulbasaur, Infernape, Sceptile - Rowlet has a defined personality that the anime takes considerable time developing.
Rowlet starts as a playful and inexperienced Pokémon that takes a relaxed approach to battling. After losing to Hau's Dartrix, Rowlet shows a desire to improve and begins training harder. Unlike some other Pokémon in the anime who showed aversion to evolving, like Ash's Pikachu or Dawn's Piplup, Rowlet seems indifferent to the concept. However, it takes a liking to an Everstone it picks up along the way, thus preventing him from evolving.
Mallow
Mallow is a friendly and energetic young girl, quick to jump to conclusions. She's also a gifted cook, like Brock, Cilan, and Clemont before her. She's a Grass-type specialist who aims to one day take over her family's restaurant, Aina's Kitchen.
Out of all the companion characters in Pokémon, Mallow has arguably the saddest backstory. She harbors a deep regret for her unkindness towards her mother, who passed away shortly after. In one of the anime's most heartbreaking episodes, she's able to reconcile with her mother's spirit, aided by the Legendary Pokémon Tapu Fini.
Professor Kukui
In stark contrast to the Professors that came before him, Kukui is younger and more laid back. He's still formal and even stoic but still enjoys telling the Pokémon equivalent of "dad jokes." He's a friendly and hospitable man who shows the same kindness to Pokémon as he does to people.
Kukui has an alter ego, the Masked Royal, The Battle Royal Dome's star Trainer. He has a record winning streak of at least 21 victories and goes to great lengths to protect his secret identity. By the season's end, however, all of Alola knows his secret.
Kiawe
Kiawe is one of Ash's most experienced and battle-hardened friends. He takes Pokémon battles very seriously and has a deep respect for Z-Rings and Z-Moves. Kiawe is considerably more mature than Ash's other classmates, often acting in a stoic and self-important manner.
He's also prideful and overconfident, although he learns how to work as a team with his other classmates. Kiawe is a Fire-type specialist who also tends to go overboard with his emotions. Once, he cries after getting the opportunity to ride a Kantonian Rapidash.
Lillie
Like Sophocles, Lillie is extremely intelligent. She possesses an almost encyclopedic knowledge about Alolan Pokémon, although she shows a surprising lack of awareness about other regions. Lillie is polite, kind, and selfless. She becomes close friends with Ash, although she shares a distant relationship with her immediate family.
Lillie also harbors a crippling fear of Pokémon after being attacked by an Ultra Beast as a child. She overcomes it by befriending an Alolan Vulpix, which she later adopts and names Snowie. Lillie also underperforms when it comes to athletic abilities and even has trouble throwing PokéBalls.