"You" (stylized as you) is Japanese artist Koda Kumi's 19th single and the first to be released in her 12 Singles Collection. It became her first single to take #1 on the weekly Oricon charts.

you is Japanese singer-songwriter Kumi Koda's first single in her 12 Singles Collection. It became her second single to debut at #1 and first to hold the #1 spot for the weekly ranking on the Oricon Singles Charts. Her first the debut at the top spot was "Butterfly," but "Butterfly" had dropped to take the number-two slot for the week.

Each single in the 12 Singles Collection had unique cover art based on certain cultures in various countries. The back cover of each single was a piece to a puzzle, which could only be completed by purchasing all twelve singles. The same was done for the obi strips, which contained a full image when arranged together in order. However, the obi strip image was omitted on the Hong Kong versions.

"you" was composed by music composer Toru Watanabe and performed by arranger and lyricist Yoko Kuzuya, who also worked on the lyrical portion with Kumi. The song carries elements of both pop and R&B, opening strong with a piano instrumental.

The single was also only one of three in the collection to garner a b-side, the others being No Regret and Someday/Boys♥Girls. The b-side for this single was "Sweet Kiss," which is an uptempo pop song. The song was composed by Atsushi Sato (known as ats-) from the Japanese pop band HΛL, who had previously worked with Kumi's label-mate Ayumi Hamasaki.

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