PUPA

PUPA was an entry in the G2R2014 ("GO BACK 2 YOUR ROOTS") BMS tournament, and it was the very first BMS Morimori Atsushi ever made, after years of doujin work. The piece was built around a short story by Saeka Uzaki, used with the author's permission: Atsushi has said he wrote the music to fit the plot and then refined the story while listening back, so narrative sits at the heart of the work. Supervision of some of the BMS charts was handled by Takeshita-dori. The track placed 22nd in the event's individual score ranking. Over the years it became Atsushi's signature and most popular song, landing on six commercial rhythm games within roughly five years.

In titles such as EZ2ON REBOOT:R, DJMAX RESPECT V and Sixtar Gate: STARTRAIL, PUPA holds the boss song slot, earning nicknames like "that butterfly" and "the butterfly that tears people apart." Its reputation swelled until players were calling it the hardest rhythm-game song in the same breath as FREEDOM DiVE. The composer leaned into the meme, even tweeting in Korean that "the butterfly tears people apart." Fittingly or not, the song's symbol is a morpho butterfly, even though "pupa" itself means chrysalis. The franchise around it includes a sequel (larva, released under the alias Garigari Samushi), many remixes, and the tenth-anniversary album PUPA -Metamorphoses-, which collects nine reworkings.

The PUPA meme had a knock-on effect inside Pump It Up: it pushed the community to rediscover older songs featuring the morpho butterfly, most notably "Final Audition Episode 2-2," affectionately dubbed the "original butterfly." In PHOENIX, PUPA offers a broad ladder of charts for every level, from an approachable Single all the way to S23 on Single and the steeper Double charts, topping out at D25. The official music video, based on the source novel, only arrived in September 2023 - nearly a decade after the track first appeared.