Default Dressphere: Gunner
In Final Fantasy X, Yuna was accompanied on her pilgrimage to defeat Sin by Wakka, Lulu, Kimahri, Auron, Rikku, and Tidus (called "him" in this game). After Yuna and her guardians finished their quest, Tidus suddenly vanished. This broke Yuna's heart, even though Tidus was only a dream of the Fayth.
Yuna became a sphere hunter with the Gullwings, after Rikku found a sphere containing pictures of what looked like "him" (Tidus). She now travels throughout Spira with Rikku and Paine, hunting for spheres, and looking for "him"...
Default Dressphere: Thief
Rikku, an Al Bhed girl, was one of Yuna's guardians in her quest to defeat Sin. Before Sin was defeated, the Al Bhed were treated like outcasts because they used machina, something that was forbidden by Yevon.
Rikku set up the Gullwings (sphere hunters) together with Brother. When she found footage of what looked like Tidus, she persuaded Yuna to leave Besaid, and join the Gullwings. Rikku's energy and optimism is endless!
Default Dressphere: Warrior
Paine is a quiet but mature sword fighter who joined the Gullwings shortly before Yuna did. She does not get influenced Rikku's silliness, and is often sarcastic when the Gullwings get too loud! She appears tough, but underneath is compassionate.
Paine does not reveal much about her mysterious past, but somehow is well known by Gippal, Nooj, and Baralai.
Leblanc The leader of the Gullwings' rivals, the "Leblanc Syndicate".
Ormi Member of the Leblanc Syndicate; a lackey of Leblanc.
Logos Member of the Leblanc Syndicate; a lackey of Leblanc.
Brother Rikku's brother, and leader of the Gullwings. Has taken a liking to Yuna!
Buddy A friend of Brother, an Al Bhed, and a member of the Gullwings.
Shinra An intelligent Al Bhed kid who works in the Celsius.
Barkeep Brother took in this Hypello, who now works in the bar and inn of the Celsius. His real name is unknown.