星屑ユートピア (Hoshikuzu Utopia, "Stardust Utopia") is a VOCALOID song by producer otetsu, featuring 巡音ルカ (Luka Megurine) as vocalist. The track first appeared in the niconico doujin music scene before becoming a cross-title staple across SEGA's arcade rhythm game lineup, debuting in CHUNITHM PLUS (April 2016), then arriving in オンゲキ PLUS (March 2019), and finally maimai でらっくす (September 2019). At 240 BPM, it is a fast-paced electronic composition driven by layered synth work and Luka Megurine's processed vocals, characteristic of otetsu's production style. The lyrics weave imagery of night skies, stardust, and unreality, opening with "今日も夜空に浮かべた非現実の中" ("Within the unreality floating in tonight's sky") and building a cosmic, melancholic atmosphere that oscillates between laughter, tears, and the act of living. In maimai DX, the song was added through the Project DIVA collaboration area (Project DIVAちほー), a limited-time event where players unlocked the track by accumulating 160 meters of distance. After the event window closed on October 31, 2019, the song became generally available from November 1, 2019, with region-specific unlock schedules for Asian and Chinese cabinets. The MASTER chart (level 12+, constant 12.7), designed by 玉子豆腐 (Tamagodoufu), is characterized by dense clusters of Touch and Break notes that demand precise spatial awareness across the full screen, while the EXPERT chart (level 10+, constant 10.6) by 某S氏 prepares players with its own high-density patterning. The difficulty levels of several charts have been adjusted across maimai DX versions, with the Basic chart dropping from 4 to 3 and the Master chart shifting between 12 and 12+ over several releases.