SPILL OVER COLORS is a maimai original song created by composer 矢鴇つかさ (Tsukasa Yatoki) featuring vocals by kalon., a singer who built their following on Japanese video-sharing platforms in the utattemita (歌ってみた) community. Added during the maimai MiLK era on April 17, 2018, the track represents a milestone for both contributors: it is Yatoki's first vocal composition for the series following his earlier instrumental contributions Fragrance and Black Out, and it also marks his first piece written directly for maimai rather than sourced from the Halfpipe Tokyo lineup. kalon., meanwhile, makes their maimai debut here. The song is a bright mid-tempo pop piece at 142 BPM, pairing kalon.'s clear vocal delivery with Yatoki's melodic production. In-game, SPILL OVER COLORS initially followed a staggered unlock path typical of MiLK-era content: it debuted as a Survival Course exclusive, became exchangeable for 5 Cheese on May 22, 2018, and was made freely available with the launch of maimai MiLK PLUS on June 21, 2018. The Expert and Master charts were designed by veteran charter はっぴー, while a Re:Master chart arrived much later, on August 19, 2022 during maimai でらっくす UNiVERSE PLUS, designed by Jack. The Master chart stands out for its slide-heavy composition (160 Slide notes out of 832 total), and the Re:Master chart's outro incorporates a signature gimmick where a single ☆ tap fans out into an extended slide pattern, a flourish it shares with the chart for 花と、雪と、ドラムンベース. The track later crossed over into SEGA's sister rhythm game オンゲキ (ONGEKI) Re:Fresh in June 2025.