壱雫空 (Hitoshizuku) is a high-energy J-rock track that serves as the opening theme for the 2023 anime series BanG Dream! It's MyGO!!!!!. Composed and arranged by hisakuni with lyrics by Masaki Fujiwara, both under the SUPA LOVE production unit, the song drives forward at a brisk 204 BPM, matching the emotional intensity of the series' narrative. The title blends the kanji for "one" (壱), "droplet" (雫), and "sky" (空), evoking the rain imagery that runs through the opening verses: Moshi kono ame ga agatte mo / Wasurezu ni aruiteku yo ("Even if this rain stops, I'll walk without forgetting"). The track is performed by MyGO!!!!!, the fictional girl band at the center of the anime, with vocals by all five members' voice actresses: Hina Youmiya, Rin Tateishi, Hina Aoki, Mika Kohinata, and Coco Hayashi. In maimai, 壱雫空 arrived as part of the BUDDiES PLUS update on March 21, 2024, available across all regions. The Expert and Master charts were both crafted by the celebrated notes designer はっぴー, whose Master chart (level 13+, constant 13.7) leans heavily into Slide notes, 92 of them, to mirror the song's surging momentum and lyrical flow. The song also appears in CHUNITHM LUMINOUS PLUS starting September 2024.