Kairi

Ahhh.... my least favorite character.
n Kingdom Hearts, Kairi is fourteen years old and living on the Destiny Islands with Sora and Riku and other children, including Selphie, Tidus, and Wakka. Kairi actually appeared on the islands several years ago and does not recall her life before then. However, she shows no real interest in returning to wherever it is she came from, and is content with her life on the Islands. Her arrival on the island spurred Riku's interest in other worlds and gave him the idea to build a raft and explore the world beyond the islands.

Soon afterwards, the storm caused by darkness sweeps away everyone from the islands and Kairi is separated from Sora and Riku. By the time Sora found Kairi, she was in a comatose state. It turned out that Kairi was a Princess of Heart originally from the Radiant Garden sent to the Destiny Islands by Ansem to confirm his theory that a Princess of Heart and the Keyblade are connected. Though Maleficent found out this fact about Kairi, her heart ended up inside Sora before their island was destroyed. Because of this, Maleficent was unable to unlock the Keyhole inside Hollow Bastion until Kairi's heart was recovered.

Kairi is saved by Sora, who gave up his heart in order to restore hers. Kairi takes it upon herself to protect Sora, showing Sora the way to the light which restored him. During the final stages of the game, Kairi remained in the safety of Traverse Town, and in the temporary care of Leon, Aerith and Yuffie. After Ansem's defeat, Kairi is left behind on the reforming Destiny Islands and separated from Sora at the end of Kingdom Hearts. Sora promises to return to her with Riku, and Kairi waits on the island for their return.