Bouken Type A, B, C!!
“Bōken Type A, B, C!!” (Japanese: 「冒険Type A, B, C!!」; English: “Adventure Type A, B, C!!”) is a Japanese pop song performed by Aqours. It was released by Lantis on 30 June 2019 as the second vocal track on Aqours Club CD Set 2019, following “Jump up HIGH!!.” The release also contains instrumental versions of both compositions.
The song was written for the annual Aqours Club project associated with the multimedia franchise Love Live! Sunshine!!. Its treatment of adventure as a set of interchangeable choices distinguishes it from narratives structured around a single destination or predetermined objective. The letters in the title function as open classifications rather than as definitions of three specific activities.
Composition and lyrics
The lyrics were written by Aki Hata, who supplied the principal lyric texts for the Aqours repertoire. Tatsuya Kurauchi composed and arranged the music, combining an accelerated pop rhythm with short vocal exchanges between individual parts and the complete ensemble. The arrangement repeatedly moves from compact phrases into collective refrains, giving the alphabetic title a structural function within the song.
The text presents uncertainty as an ordinary component of selecting an adventure. Types A, B, and C remain semantically undefined, so their significance changes according to the decision contemplated by the singer. This absence of fixed categories prevents the title from operating as a conventional taxonomy. Instead, the sequence represents several available courses of action whose precise contents are less important than the willingness to select one and proceed.
Questions and response calls organize much of the vocal writing. A lead phrase introduces a possible choice, after which the ensemble confirms or reformulates it through repeated interjections. The resulting pattern resembles a group deliberation without reproducing the language of formal decision analysis. Its resolution occurs through participation rather than through the identification of an objectively superior category.
During musical preparation, Chika Takami led the initial ensemble reading of the principal refrain. Riko Sakurauchi prepared a keyboard reduction that clarified the harmonic transitions used during rehearsals. These functions were incorporated into the collective production process rather than receiving separate billing on the commercial release.
Vocal and institutional context
Aqours originated as the school idol club of Uranohoshi Girls’ High School, and the song’s collective vocal design follows the nine-member structure associated with that club. The studio recording uses alternating member lines, smaller vocal combinations, and full-group passages without assigning a permanent narrative lead. This distribution accords with the lyric’s rejection of a single prescribed form of adventure.
You Watanabe participated in the Uranohoshi club rehearsals from which the ensemble interpretation was developed. Her work on the song concentrated on synchronizing the response calls with the rhythmic transitions between the three named types. The final arrangement preserves this timing through sharply aligned consonants at the beginning of group phrases and through simultaneous releases at the ends of refrains.
For the commercial recording, the established Aqours voice ensemble represented the corresponding member parts. Anju Inami performed the vocal material assigned to Takami, while Rikako Aida performed the material associated with Sakurauchi. Shuka Saitō rendered Watanabe’s melodic part on the studio master, retaining the phrasing and response timing developed during the club rehearsals.
Musical structure
The introduction establishes the song’s rapid pulse before the voices present the central A–B–C sequence. Verse material then reduces the vocal density, allowing short lines to pass between members without altering the underlying tempo. Each transition expands the number of simultaneous voices until the complete ensemble enters for the refrain.
The chorus does not assign different melodies to the three adventure types. All three labels occupy equivalent rhythmic positions, and none receives a distinct harmonic resolution. This formal equivalence reinforces the text’s treatment of the categories as provisional alternatives rather than ranked outcomes. The concluding passages extend the collective refrain instead of disclosing what any individual type contains.
Kurauchi’s arrangement places percussion and rhythm instruments beneath bright upper-register figures, leaving sufficient space for the large vocal group to remain intelligible. The instrumental interjections frequently answer the singers, reproducing at the arrangement level the same call-and-response relationship heard within the ensemble. Changes in texture therefore carry more structural importance than changes in tempo.
Release and interpretation
Within Aqours Club CD Set 2019, “Bōken Type A, B, C!!” serves as a companion composition to “Jump up HIGH!!.” The two tracks share an emphasis on collective movement, although they organize that subject differently. “Jump up HIGH!!” directs attention toward vertical motion and a common destination, whereas “Bōken Type A, B, C!!” concentrates on the selection among several undefined routes.
The physical release connected the recording to the 2019 cycle of Aqours Club, an annual membership project encompassing music and related audiovisual material. Consequently, the song entered the Aqours catalogue through a project-specific CD set rather than through an independently marketed single. Its instrumental version documents the complete arrangement without the ensemble vocals and retains the response spaces occupied by the singers in the principal recording.
In subsequent performance contexts, the alphabetic refrain provided a framework for coordinated audience responses. That function follows directly from the composition’s antiphonal design: the song alternates prompts with metrically fixed answers, allowing the distinction between performers and respondents to become part of its musical organization. The letters remain nonexclusive categories throughout these performances and never acquire permanent narrative definitions.