"Gekkō" (月光, Moonlight) is a song by Japanese singer-songwriter Chihiro Onitsuka from her debut album Insomnia (2000).

[2] "Gekkō" debuted at number thirty on the Oricon Weekly Singles chart and peaked at number eleven, due to the unexpected hit of the television drama series Trick.

In January 2014, the song charted at number fifty-eight on the Billboard Japan Hot 100 chart, as the song was used in television commercial for the Japanese film Trick The Movie: Last Stage, the last installment of the Trick series.

[3] The music video was released on June 24, 2011, via Onitsuka's Vevo account.

[4] It was directed by Tsuyoshi Inoue and primarily features Onitsuka singing in front of a Christian cross.