Final Fantasy X is arguably the best title in this historic video game franchise, and that comes thanks to a cast of extraordinary characters. On a quest to save the world (as with every Final Fantasy ever), the player takes control of the young and remarkably immature Tidus, who has his own story to fulfill on this quest.
In typical Final Fantasy fashion, the playable characters grow into a team of varying talents, and there are plenty of side characters to interact with along the way. This lends itself perfectly to the trend of sorting characters into Hogwarts Houses.
Here is where everyone from Final Fantasy X would have ended up.
Braska—Gryffindor
Just about any summoner would qualify as a Gryffindor (keywords: just about). The nature of them is to sacrifice themselves for the good of the world. Braska fits that mold. He loves his family, he sees through race and creed, he cares and fights for his guardians.
There's a reason that his trifecta with Jecht and Auron worked so well and didn't need anymore—these were three powerful Gryffindors. At least at the time. Auron has since been transferred to another house. More on that later
Jecht—Gryffindor
Jecht is pretty much Gryffindor on steroids. He's driven, ambitious and courageous, but along with it, he is incredibly selfish, brash and over-confident, but such is often the side effects of being one such as he is.
However, even in spite of this surface persona dominating who he is, there is a softness and love underneath. Even though he's hard on Tidus, he loves him and wants only what's best for him. He's interested in what the right thing to do is, a sentiment that Tidus later repeats without knowing that his father said it as well. That's about as Gryffindor as it gets.
Seymour—Slytherin
Any time world domination is involved, it's a safe bet to sort the culprit into Slytherin, even if their decor and color scheme is more applicable to Ravenclaw. Seymour, at first, comes across as depressing and nihilistic, but he later turns out to be as cruel and self-serving as they come. His ruthless ambition reaches its peak when he proposes to Yuna, solely with the hopes of adding her powers to his own arsenal. This man is all the worst parts of Slytherin and it leads to his ultimate downfall. Voldemort anyone?
Kamahri—Gryffindor
Built by a quest for honor and loyalty to his friends, Kamahri is Gryffindor through and through. While he does lack the boisterous side of his house, he makes up for it with a bravery that is unmatched. Any time there is trouble, the Ronso is first into the fray. He will do anything for Yuna, even die for her if it was asked of him. Those are the principles Gryffindor house is built on.
Rikku—Hufflepuff
Easy-going, caring, energetic and loyal to those she cares about. Rikku is just one of those bubbly people that everyone wants to be friends with. She isn't driven to be the best at any particular thing, she isn't selfish or arrogant or blinded by hatred.
She just cares a lot about a lot of things. She's loyal to her new party of friends and to her family and her only real flaw is that she cares too much about other people and rarely has time to focus on herself.
Auron—Ravenclaw
Auron is a tough one to place because of the person he has become. In his youth, he'd have been a Gryffindor, same as Jecht and Braska. They were the perfect brazen guardians for Braska to complete his pilgrimage. But having grown through that time, Auron has since changed, and where he would be sorted now is drastically different, seeing as how he has had his self-confidence shattered, though he still retains that stoicism.
As such, it's best to place him in Ravenclaw, where stoicism and wit rule the day. He is the voice of reason in nearly every crossroads.
Lulu—Ravenclaw
Quiet. Intelligent. Powerful. That is Lulu. She rarely smiles, but she has a sharp wit bred by a remarkably sharp mind. A perfect example of a foil, her and Wakka are complete opposites and it allows Lulu's traits to shine through all the brighter.
Thus, she is an easy Ravenclaw. She's stern and resolute in her decision making, and it's all geared towards succeeding. Perhaps the only thing separating her from Slytherin is her dedication and love for those that could be construed as lesser than her, also known as Wakka and Tidus.
Wakka—Hufflepuff
Despite looking like a Gryffindor thanks to his orange cockatoo haircut, Wakka is distinctly Hufflepuff. This shines through bright and clear with his motto as captain of the Besaid blitzball team. He just wants them to do their best, not necessarily win. This automatically disqualifies him from Slytherin or Gryffindor.
He's also really good-natured, he's a loving, loyal man, and he's just an overall good guy and huggable goofball. The best place for some like that is the house of the badger.
Yuna—Hufflepuff
All of Yuna's personality traits mirror precisely what is found from the typical Hufflepuff. She is the kindest member of the group by a long-shot, even finding kindness in her heart for young Tidus and helping him grow into a better person as they become a perfect foil for each other.
She's also loyal, not just to her group, but to the world that she strives to save through a journey of sacrifice. She's polite, she's focused on the cause of being a summoner. She could be the emblem of Hufflepuff. She's also the beacon that has pulled so many other Hufflepuffs to her guardians.
Tidus—Gryffindor
Tidus had Harry Potter syndrome, sitting on the fence between Slytherin and Gryffindor. He's quite selfish at times, quite selfless in others. He's arrogant, which goes both ways, and he's often brash and doesn't think things out. Which is what gave him the slight nudge over to Gryffindor.
Tidus's inferiority complex built by his father makes him even more driven to become the best at something—anything. While not 100% Gryffindor, the fact that he makes the ultimate sacrifice, in the end, is all the confirmation needed that he's of the lion.