MilK is a Future Bass instrumental by the prolific BMS and rhythm-game composer モリモリあつし (Morimori Atsushi), originally submitted to the 大血戦, THE BMS OF FIGHTERS ULTIMATE (BOFU2015) contest, where it placed 9th overall. The track was added to maimai at the launch of maimai MiLK, the version edition whose name mirrors the song's title, making it one of the few maimai songs whose name closely echoes the version it debuted in. Built around a bright, driving synthesizer melody at 150 BPM, MilK channels the mid-2010s doujin Future Bass sound with pitched vocal chops, layered synth pads, and crisp percussion. The track is purely instrumental, letting its production details carry the energy without lyrics. An extended version, "MilK (Extended Mix)," appears on Morimori Atsushi's album タイムカプセル (Time Capsule), alongside a remix by AMAZE. A sequel track titled "TeA" later appeared in SEGA's ONGEKI PLUS, and a 10th-anniversary remix album, "MilK 10TH ANNIVERSARY," gathered contributions from artists including EmoCosine, linear ring, Zekk, Frums, and others. In maimai, MilK has remained playable across all regions since its debut, and its charts have undergone several level adjustments over successive version updates as the game's difficulty curve evolved. The Master chart, designed by 小鳥遊さん (Takanashi-san), and the Expert chart, designed by rioN, are both dense patterns characteristic of the MiLK-era upper-difficulty range. The song was also featured in the 白十段 (White 10th Dan) course alongside other demanding tracks, cementing its place in the game's mid-core to hardcore repertoire.