⅓の純情な感情 by SIAM SHADE

"1/3 no Junjō na Kanjō" (1/3の純情な感情, "1/3 Pure Heart Emotion") is a song by the Japanese rock band Siam Shade, released in 1997. The song was first released as their sixth single on November 27, 1997, and also featured on their fourth studio album Siam Shade IV - Zero, released on January 21, 1998. It is the band's best known work and best-selling single, reaching number three on the Oricon chart, and was the 31st best-selling single of 1998 with 698,520 copies sold. By 2016, this number had grown to over 800,000 copies. The title song was used as the sixth ending theme of the Rurouni Kenshin anime. The single was reissued in the standard 12 cm CD format on November 14, 2007.