planet dancer is an original maimai track by Hiroshima-born singer-songwriter Eiichiro Taruki (樽木栄一郎), best known in rhythm-game circles for his contributions to Konami's BEMANI series, most notably "I'm a loser," "Mr.bobby," and "PUZZLE." The song debuted in maimai ORANGE on December 18, 2014, marking Taruki's return to game music after roughly a decade away. He has described the track as a spiritual sequel to "I'm a loser," carrying forward that song's theme of solitude and self-confrontation, but wrapped in a knowingly cheesy, 80s-tinged dance arrangement. The title evokes "tripping to an unknown planet inside your heart," a sentiment mirrored in the official music video directed by Kazuho Shirai (白井一歩) and starring Daisuke Kurata (倉田大輔). Taruki recorded the vocals, acoustic guitar, electric guitar, and drums live, programming the remainder of the arrangement. Across its five Standard-format charts, planet dancer has been handled by several of maimai's distinguished notes designers. The Expert chart is a collaboration between rioN and はっぴー (credited jointly as "合作だよ" before maimai PRiSM PLUS); the Master chart, designed by はっぴー alone, is notable for containing zero Hold notes across its 549-note count, an unconventional touch that foregrounds Slide and Tap patterns. The Re:Master chart, added during maimai でらっくす Splash in November 2020, was designed by ロシェ@ペンギン (Rocher@penguin) and raises the density to 732 notes at a 13.7 constant. Originally locked behind a music-ticket purchase (200 tickets at launch, later reduced, then freed entirely in maimai PiNK), planet dancer is now available by default across all regions including Japan, international, USA, and China.