From Final Fantasy Wiki

Wantz

"Welcome to O'aka's!"

—Wantz

Wantz is the little brother of O'aka XXIII in Final Fantasy X. He appears at seemingly random times in the game to take pictures of Yuna. At the Moonflow, he's seen being bullied by Biran Ronso and Yenke Ronso. After Yuna is branded a traitor of Yevon, Wantz's brother is imprisoned for helping Yuna, and he decided to take over his business as a merchant.

He and O'aka had a sister who was a summoner. She passed away approximately seven years before the events of Final Fantasy X. If the player revisits the Farplane just after the initial events there, before heading on to the Thunder Plains, they can find Wantz talking to her there. He shows her a sphere of Yuna and says that they look alike. He promises that Yuna will beat Sin for her.

During the Eternal Calm, O'aka and Wantz had a feud, and Wantz was kicked out of the family business for believing that the Macalania Travel Agency would fail without the Temple. However if the Gullwings complete all of O'aka's side-quests, he and Wantz will reunite at the Agency, although their feud doesn't seem to be over.

Trivia

• Wantz is by far the most important merchant for those that trying to customize good weapons and armor. After going through Mt. Gagazet the first time, if the player talks to him, he will than appear at Macalania Woods entrance selling empty four slotted weapons and armor for the part. It is crucial to talk to him the on Mt. Gagazet though or he will not appear.

Other Appearances

Wantz, as a little boy, makes an appearance in Kingdom Hearts II as a merchant in Twilight Town, along with Biggs, Wedge and Jessie from Final Fantasy VII.