Aoi Takahashi, a second-year Tousei High School student, initially disdained school clubs as breeding grounds for hollow camaraderie. Lured into the Tesaguri Club by ex-president Mio Watanabe under a one-year trial to confront her skepticism, she gradually bonded with members, immersing herself in activities while seasoning brainstorming sessions with pun-driven humor.

Bluntly critical of other clubs—often dismissing their efforts as “annoying”—she channels her fear of heights into devising hypothetical scenarios, such as blending Twister mechanics into shogi or inventing rugby variants with surreal objectives like synchronized cartwheeling.

During the second season, she collaborates with Koharu on meta-narrative strategies to sustain the club post-graduation, dissecting timeline inconsistencies and retroactively adjusting calendar dates to preserve group cohesion. Her interactions brim with lighthearted jabs at peers’ traits, including chest-size teasing, framed as jovial ribbing rather than malice.

Raised by her grandmother, her dialogue occasionally surfaces outdated cultural references. Though pragmatic about club endeavors, her early cynicism now coexists with fervor for unorthodox experiments. No confirmed details exist about her presence beyond the television series.