"Luminous" (ルミナス, Ruminasu) is a pop song by the Japanese duo and idol unit ClariS, written by Shō Watanabe. It was released as the unit's sixth single on October 10, 2012 by SME Records. The song was used as the opening theme to the first two Puella Magi Madoka Magica anime films. A music video was produced for "Luminous". The single peaked at No. 4 on Japan's weekly Oricon singles chart, and was later awarded a Gold Disc by the Recording Industry Association of Japan for having exceeded 100,000 copies shipped in a single year.

"Luminous" is a J-pop song with instrumentation from piano, violin and drums. It is set in common time and moves at a tempo of 173 beats per minute. Beginning in the G major key, the introduction starts with only piano and adds drums and violin to transition into the first verse in C-sharp minor, followed by the chorus. After a bridge in G major, the key shifts back to C-sharp minor for the second verse and chorus, which use the same music with different lyrics. The key shifts from C-sharp minor to G major with a short break used to transition into the third verse, immediately followed by the chorus in C-sharp minor as the outro. A short coda is used to close the song.

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