KOKIA

Akiko Yoshida (?????, Yoshida Akiko?) is a Japanese singer-songwriter, who performs under the stage name Kokia (stylised as KOKIA). She is best known for her songs "Arigat?..." (?????..., Thank You?) (which reached number 1 in Hong Kong when it was covered by Sammi Cheng) and "The Power of Smile." She is also recognised for her numerous contributions to animeCh?wa Oto (With Reflection)" for the film Origin: Spirits of the Past, "Follow the Nightingale" for the game Tales of Innocence, and "Tatta Hitotsu no Omoi" for the anime Gunslinger Girl: Il Teatrino.

source: Wikipedia