Aoi Inuyama co-founded the Outdoor Activities Club at Motosu High School with her childhood friend Chiaki Ōgaki. She possesses distinctive thick eyebrows visible beneath hats and reveals a sharp fang when smiling or speaking. Her appearance features chest-length greenish-brown hair, fading lighter at the ends, typically styled in a left-sided ponytail secured by a purple hair tie, and olive-green eyes. For outdoor excursions, she wears a grey-and-white scarf, a light-blue sweater over a dark-blue shirt, a multicolored skirt, and brown boots, switching to the standard female school uniform during classes. She speaks with a noticeable Kansai dialect, tracing it to her birthplace in Inuyama, though references vary between Aichi and Gifu Prefectures.

Her personality blends approachability with a penchant for playful deception, often inventing tall tales or exaggerating stories for amusement—a harmless family habit detectable to friends through her darting eyes or vanishing irises. She maintains a calm, grounded demeanor, acting as a voice of reason that balances her clubmates' energy. Academically proficient within the club, she diligently works part-time as a cashier at Zebra Shop supermarket to fund club trips. She demonstrates culinary skill, particularly with Kansai-region dishes, and enjoys cycling to school on a road bike gifted by a relative.

Family relationships significantly shape her character. She shares a close bond with her younger sister Akari, who affectionately calls her "Aoi-chan"; their interactions include lighthearted exchanges like comparing meats for family recipes. Her grandmother influenced her name, choosing "Aoi" in hiragana to avoid unintended kanji readings like "Dog Wasabi." Family interactions reveal a shared inclination toward humorous storytelling, exemplified when her claim of a traditional "Soba Cormorant Bowl" backfires during a flower-viewing event.

Ten years after high school, featured in the Laid-Back Camp movie, she works as an elementary school teacher at Fujikawa Elementary in Kajikazawa, earning the nickname "Aoi-chan" from students and occasionally weaving playful fabrications into lessons. When the school faces closure, she secures a position elsewhere in Yamanashi Prefecture, residing with her family. During this time, she assists Chiaki's campsite development project, contributing scheduling expertise and proposing a dedicated children's area. After the project's suspension, she helps salvage materials, repurposing old tires from her former school for the kids' zone. By this period, she obtains a driver's license and operates a Honda N-one vehicle.

Her birthday is March 4, shared with clubmate Nadeshiko Kagamihara and historical figure Heihachiro Oshio. Chiaki nicknames her "Inuko" (dog girl) after misremembering her surname. She harbors fondness for Caribou-kun, mascot of an outdoor gear shop, and enjoys reading about bivouacs while disliking disruptions to her comfort. Online popularity surged for her following an anime hot springs episode. A dedicated four-panel comic strip, "Inu-Inu-Inuko-san," appears in manga volumes, humorously exploring aspects of her background.