"Karma" is a song by Kokia, released as her 20th single on April 22, 2009. It was used as the first opening theme song for the anime Phantom: Requiem for the Phantom, and would later feature in an edited version on the anime's soundtrack. Her song "Transparent" would be used as the second ending theme song for the same anime.

The song was covered on the album Exit Trance Presents Speed Anime Trance Best 8 by MK feat. R. Cena, later in November 2009.

"Karma" was released only a month after Kokia's 9th and 10th studio albums Kokia Infinity Akiko: Balance and Akiko Infinity Kokia: Balance. The single was her first release through anime retailer Lantis, as opposed to her usual release label Victor Entertainment. Kokia had released game/anime theme songs on a different label twice in her career: once through Victor Entertainment in 1998 while she was still signed to Pony Canyon ("Ai no Field" for anime Brain Powerd) and once through Marvelous Entertainment in 2008 ("Tatta Hitotsu no Omoi" for Gunslinger Girl: Il Teatrino).

Kokia had sung many songs for anime in the past. This was the third time her music had been used as an opening theme, after "Chōwa Oto (With Reflection)" in 2006 for the film Origin: Spirits of the Past, and "Tatta Hitotsu no Omoi" for Gunslinger Girl: Il Teatrino.

"Karma" was recorded in January 2009, while Kokia was recording Kokia Infinity Akiko: Balance and Akiko Infinity Kokia: Balance. The song was recorded with a 4422 string section, a type of string arrangement featuring four lead violinists, four secondary vilionists, two viola players and two cellists. The song has Kokia's vocals layered twelve times to create the background vocals. The single's B-side "Insonnia" was recorded by Kokia on March 24.

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