Ai Inō is a fair-skinned young woman with long light brown hair usually worn in a ponytail and dark yellow eyes. She wears an orange zip-up jacket with white stripes on the sleeves, dark green cargo shorts, ankle-high white socks, and white-and-blue sneakers.

Her personality is upbeat and positive, with a strong belief in collaborative group efforts. This is demonstrated when she intervenes to resolve conflicts among peers, such as breaking up a classmate argument, and actively aids group navigation by marking their position on a map to prevent disorientation.

Ai was a second-year student at Houshou Private High School and a member of its hiking club.

Her story arc culminates in an early, fatal incident. After marking the group's location, she separates to relieve herself and notices giant *Papilio maackii* butterflies. Initially unconcerned, she becomes alarmed as they approach due to their immense size. Attempting to crawl away, she is immobilized by one butterfly inserting its proboscis into her vulva. Simultaneously, a second butterfly stabs her in the right side of her head. Both drain her bodily fluids, causing rapid desiccation and death while she pleads for help.

In the anime adaptation, the first butterfly stabs her left buttock and the second inserts its proboscis into her mouth. Across all media, including sequels and spin-offs like *Die! The Island of Giant Insects* and *Mountain of Giant Insects*, her role remains confined to this single appearance and fate.

Her name combines "Ai" (愛 - love, affection) and "Inō" (伊野 - that one, plains/rustic).