Sunao na Niji (素直な虹)

"Sunao na Niji (素直な虹)" is a song by surface that appeared as an ending theme for Naruto (ナルト), the television anime produced by Studio Pierrot. surface released it as the duo's 17th single on November 10, 2004.

椎名慶治 wrote the lyrics, 永谷喬夫 composed the music, and surface arranged the song. It later appeared on ROOT, surface's fourth original album, released on February 23, 2005, and the single also included "ドラマチック" and "season's" as its coupling tracks.