Kairi - Yenra Picture Wiki
Kairi is an original character created by Tetsuya Nomura for the Kingdom Hearts series.
She is Sora and Riku's best friend, and one of the seven Princesses of Heart. Nomura has stated that Kairi's name can be interpreted as "sea"; the Japanese on'yomi pronunciation of sea is kai.
During Kingdom Hearts, Kairi's heart enters Sora's while her body falls into a deep sleep when Destiny Islands is destroyed by the Heartless. Upon learning her identity as a Princess of Heart and the location of her heart, Sora gives up his heart in order to release hers and restore it back into her body. Soon after, Kairi finds Sora's Heartless and restores him back to human form. Kairi later stays in Destiny Islands awaiting Sora's return from his journey.