Ayu Daikuuji, daughter of the CEO of the "Sky Temple" financial group, works undercover at one of its family restaurants as part of a market study, concealing her privileged identity. This position allows her firsthand operational experience within her family's business.

Primarily a supporting character providing comic relief, she works alongside Takayuki Narumi and Mayu Tamano. Her humorous interactions with Mayu feature prominently in the "Ayu-Mayu Theater" – super-deformed comical vignettes appearing after credits in several television episodes, separate from the main plot.

In the OVA *Kimi ga Nozomu Eien: Next Season*, she retains this established supporting role. Ayu possesses a surly, occasionally irritable, and mischievous personality. Her visual design is marked by distinctive pigtails and a notable snaggletooth. Her first name, "Ayu" (あゆ), is written in hiragana.

Beyond her restaurant duties and comedic segments, documented media across the primary series, OVAs, and referenced spin-offs provide no significant character development, backstory expansion, or focused narrative arcs for Ayu. Her appearances in games like *Ayu-Mayu Alternative* and *Daikuuji Temple in Crisis!* are noted, but specific character details or evolution within them are not provided; her role remains consistently secondary, supplying levity within the broader dramatic narrative.