Originally one of Azula's right-hands and an enemy of Team Avatar, Mai had a change of heart in the waning years of Avatar's Hundred Year War. Betraying the Fire Nation, Mai saved the lives of Prince Zuko, Sokka, Suki, Chief Hakoda, Chit Sang, and her own uncle before Azula imprisoned her. Allowing Firelord Ozai's defeat, Mai continued to act as an ally of Aang and co., even assisting them in a few missions.
Known for her mostly deadpan attitude and gloomy disposition, Mai often took a bit to warm up to others but quickly formed bonds with even the most unlikely people.
10 Get Along With: Grim (The Grim Adventures of Billy & Mandy)
The feared and infamous Grim Reaper, Grim found himself a servant of two children — Billy and Mandy — following his loss at a limbo game for the soul of Billy's hamster. Though he wields considerable underworldly powers, he is bound by contract to bend the knee to every single one of Billy and Mandy's whims.
Aside from digging Grim's whole getup, Mai would no doubt sympathize with Grim's situation. She'd probably try to help him find some loop-hole in his contract and join him for when he needed to fulfill his reaping duties or anytime he wanted to pull some scaring pranks on others.
9 Hate: Wander (Wander Over Yonder)
A seemingly ancient, intergalactic traveler, Wander is an optimistic, friendly, and excitable humanoid who can't help but assist others. Quite literally incapable of doing otherwise, Wander has stated: "When I see someone who's a-needin', I just gotta help!" His trusting and good-hearted nature have often been taken advantage of, and some, like Lord Hater and Lord Dominator, simply just can't stand how happy he is all the time.
Mai herself would probably dislike how overly optimistic Wander is, wondering just how in the world he could keep being nice to everyone and everything he encountered, no matter how badly they treat him. Sure, Mai gets along well enough with Aang and Ty Lee, but they seem to know how to keep their happiness at a "tolerable level."
8 Get Along With: Emerald Sustrai (RWBY)
Once an enemy of team RWBY and an ally of Cinder Fall, Emerald Sustrai is a former thief who became disillusioned with her actions after witnessing the destruction and harm they'd wrought on thousands of innocent people. Most recently helping to take down James Ironwood after his descent into tyranny, Emerald is well on her way to the path of redemption.
Mai would heavily relate to Emerald, and understand the kind of situation she was in (as they both escaped their abusers), and would respect Emerald for deciding to do the right thing for a change. Emerald would likewise find Mai's history, personality, and abilities respectable, and they'd probably end up pulling pranks on Zuko using Emerald's Semblance.
7 Hate: Courage (Courage The Cowardly Dog)
The titular character of the 1999 series, Courage is a highly intelligent dog who lives out in the middle of nowhere (which is also the name of the official name of the area he's in). Living with his owners, named Eustice and Muriel Bagge, Courage protects them from supernatural and otherworldly entities — all of whom terrifies him.
Mai wouldn't have too much patience for the way Courage conducts himself, and would probably keep the most controlled and cool demeanor in the face of the show's monsters. She might not enjoy herself, but seeing her so nonchalantly deal with Courage's problems with her deadpan expression would make for great entertainment.
6 Get Along With: Odd Della Robbia (Code Lyoko & Code Lyoko: Evolution)
Hailing from the beloved French animated series Code Lyoko (and its follow-up, Evolution), Odd is a member of the self-styled Lyoko Warriors. Together with his closest friends, he helps protect the world from an entity known as X.A.N.A., an autonomous multi-agent system with the sole desire to escape the virtual world of Lyoko and destroy humanity.
On the surface, Odd and Mai look like they'd clash like water and oil. Odd's known to be extremely flamboyant, energetic, and very flirtatious. Mai's reserved, often stoic, and usually keeps herself speaking at a monotone level. However, it's important to note that Mai's best friend is Ty Lee — probably the most energetic and bubbly person in the entire Avatar franchise. Furthermore, Odd is more than capable of being more serious when he wants to. They'd probably end up swapping marksmanship tips.
5 Hate: Pearl (Steven Universe)
A member of the Crystal Gems, Pearl was once the second in command to Rose Quartz/Pink Diamond, acting as her personal bodyguard and confidant during The Rebellion against the Homeworld Gems. Pearl also takes her duty very seriously and has quite the perfectionist streak, often going out of her way to put things in their proper place.
Mai's rather laidback and careless personality would probably get on Pearl's nerves (similar to how Amethyst's did in the earlier season of SU), and Pearl's occasional nit-picky attitude and bragging habits would no doubt cause Mai to disregard anything the Gem said. Though Mai might think Pearl's actions as a rebel were respectable, she'd still find her overall personality too much to bear.
4 Get Along With: Raven (Teen Titans)
Daughter of the interdimensional demon Trigon, Raven is a powerful sorcerer and empath, arguably the most powerful person on her team. Her abilities directly stem from her emotions, meaning that the more she feels, the more energy she releases. As a result, Raven must constantly concentrate on keeping herself in control.
The pair would have plenty of things to bond over. Their shared sense of gothic fashion, their love for more "gloomy," darker things, and how they can only tolerate loud amounts of happiness in small doses. Mai would also likely help Raven deal with Cyborg and Beast Boy's pranking antics (much to a terrified Beast Boy's sorrow).
3 Hate: Adrien Agreste/Chat Noir (Miraculous Ladybug)
The crime-fighting partner of Ladybug, Chat Noir, is the superhero alias of supermodel and student Adrien Agreste. Gaining his powers and costume from the Cat Miraculous, Adrien wields the power of Destruction, acting opposite to Ladybug, who controls life and luck. Additionally, Adrien is also a highly skilled fencer, martial artist, and acrobat.
Though Mai might be able to handle one cat-boy, her patience would be at an end with Chat Noir far quicker than it would be with Odd. Though the two are quite similar, Chat's constant puns would undoubtedly put him in Mai's less-than-friendly crosshairs.
2 Get Along With: Amity Blight (The Owl House)
One of the main characters of The Owl House, Amity, is considered a magical protegée, coming from a prestigious and long-line of highly respected witches. Most proficient in the track of Abomination magic, Amity can construct giant, purple g00-like monsters to do her bidding.
Both Amity and Mai are rather aloof on the surface, but around the right people, they're huge softies at heart. They'd likely bond over the way that their significant others bring out the best in them, and Mai would probably even offer Amity some advice about how to best be forward with Luz.
1 Hate: Link (The Legend of Zelda [1989])
This particular entry might not be fair in the slightest. After all, who actually likes the Link that appeared in the short-lived, thirteen-episode series based on the iconic Nintendo franchise? He may have been slightly more bearable than the version of Link in the CD-i games, but that's hardly a high bar in the first place.
One drawn-out and annoying "Well excuse me, Princess!" from Link would be enough for Mai to glare daggers at him — and then throw them accordingly. She'd be even angrier with him if she knew what other versions of Link are like, and may feel like she was doing the world a service by getting rid of him.