"Ututu" is an original song created for maimai でらっくす PLUS by Japanese composer and arranger Masato Nakayama (中山真斗). The track features vocals by maimie, whose involvement was confirmed via social media the day after the song's in-game release. This marked Nakayama's first composition for the maimai series, though he had previously contributed to Sega's other rhythm game O.N.G.E.K.I. with "ポケットからぬりつぶせ！" and had sung chorus on another maimai original, "でらっくmaimai♪てんてこまい!." The song was introduced on July 3, 2020, as part of the Mikangaoka Area: Moonlit Night Avenue (みかんヶ岡ちほー 月夜通り) event, requiring players to reach a cumulative distance of 4000 meters in the area to unlock it. It later became generally available from the Splash PLUS update onward. The jacket artwork and in-game movie were handled by Gunjou licorice (群青リコリス) with illustration by Daisuke Richard (ダイスケリチャード). At a brisk 172 BPM, the Master chart, designed by ぴちネコ (Pichineko), carries a difficulty constant of 12.9 (12+) and features an unusually high Touch note count of 123, giving it a distinctive play feel compared to other charts of its level. The Expert chart, crafted by はっぴー (Happy), sits at level 10 with a constant of 10.2. The lyrics, written by Nakayama himself, paint a dreamy, nocturnal scene, addressing solitude, desire, and the tension of connection under the night sky, sung in a soft, airy delivery by maimie.