Eiko Carol is the small, summoner child of Madain Sari. She is assumed to be the last of her people, until it is discovered that Garnet, too, is from the summoner race. Eiko is young, maybe 10 years old at the time of the events in Final Fantasy IX, and has 2 distinct features. One is the small horn located on her forehead, and the other is the little pair of wing ornaments on her back.

Zidane and the party first encounter Eiko in Conde Petie, a small suspended village on the Outer Continent. She and her trusty moogle companion, Mog, were notorious thieves in the area. When Zidane catches her, she is stuck on a branch on the Mountain Path leading to her home. She falls for Zidane, who is much older, and decides to join the party, forcing herself in. She quickly attaches to Vivi as a friend, and offers him advice and companionship during his rough times.

It is discovered during their travel towards Madain Sari that Eiko can summon Eidolons, much to the surprise of Garnet. Eiko has far less Eidolons to summon, but makes up for it with stronger white magic spells. It's apparent that she has the ability to communicate with Eidolons thanks to her horn, something that Garnet does not have. It is thanks to Eiko that the party can get into the Iifa Tree. She helps defeat the creator of Mist, and then cooks up a nice meal for the party, hoping to impress Zidane more than ever.

Trouble starts when Lani the bounty hunter shows up, and kidnaps Eiko. Eiko is returned safely, in exchange for the royal pendant Garnet possessed. Luckily Amarant saved it for them. After another trip to the Iifa Tree to take on Kuja, they return to Alexandria. Eiko had never seen such a place, and was wowed by it's size and how busy it was. She ends up meeting Dr. Tot, and he asks her questions related to her people and home. In exchange, she gets him to write her a love letter to Zidane, which results in a very big mix-up involving Steiner, Beatrix, Marcus, and Blank.
After the mix-up, a very upset Eiko demands that Dr. Tot take her to Treno to finish his questioning. Here she discovers through Mog that trouble is brewing in Alexandria, and it is because of this that they arrive in time to help Garnet and the the Alexandrians fend off Kuja's Mistodons and Bahamut. As the Hilda Garde 2 passes over the city, Eiko jumps off, meeting with Garnet on top of the castle, where they commence the summoning of Alexander, via the Holy Judgment.
 
When the party heads to Kuja's Desert Palace, she gets kidnapped along with the group. While Zidane is away in Oeilvert, she leads the magic-oriented party through the palace, and helps take on Kuja's defense guard. After teleporting to Kuja's room area, she gets shut out of his room, and is kidnapped by Zorn and Thorn.

Later on, Eiko is kidnapped by Kuja and his followers, and is to be used to obtain Eidolons from her body, like what was done to Garnet. It didn't work, with Mog saving Eiko by turning into her true form as the Eidolon Madeen. Eiko loses a great friend, but gains a powerful ally.
 
From here the party begins their hunt for Terra, where Eiko is partnered up with Garnet (mostly by her own demand) to take out the Water Shrine. Here she attempts to do some "girl talk", and figure out just what Garnet's feelings for Zidane really are. However before she can get any answers Zidane and the party return to pick them up, leaving Eiko disappointed.

In the end, Eiko helps the team defeat Kuja and Necron, saving the world. In the final scene, Eiko ends up being adopted by Regent Cid and his wife Hilda, and she lives in Lindblum with them, visiting the other party members whenever possible.

Abilities:

Eiko has two principal abilities, being White Magic and Summoning, much like Garnet. White Magic is her forte, she being able to use the strongest spells. She is sort of the opposite of Garnet, who is more Summoner-oriented.

White Magic ("*" = Eiko only):

• Cure
• Cura
• Curaga
• Regen
• Life
• Full-Life*
• Panacea
• Stona
• Esuna
• Shell
• Protect
• Haste*
• Silence
• Mini
• Reflect
• Float
• Dispel*
• Might*
• Jewel*
• Holy*

Summons:

• Carbuncle - Reflect on entire party

1. With "Emerald" - Haste on entire party
2. With "Moonstone" - Protect on entire party
3. With "Diamond" - Vanish on entire party

• Fenrir - Earth damage

1. With "Maiden Prayer" - Wind damage

• Phoenix - Fire damage; revives KO'd party members
• Madeen - Holy damage

Equipment:

Eiko uses Flutes as her primary weapon. However, she can also share rackets with Garnet, which can provide her with her strongest weapon (in terms of attack power) the Tiger Racket. Otherwise her strongest Flute is the Angel Flute (which provides her with Holy). She also equips light armor, or "women's armor" (the armor only female characters, and Quina, can use).