Kuon manifests as a small, spectral entity—a floating figure defined by two luminous eyes and clothing, with no discernible physical body beneath. This being acts as Akari's primary caretaker, the central character uncovered under enigmatic conditions. Naturally levitating, Kuon employs sharp tentacle-like appendages for practical duties, including transporting items and precisely peeling fruit rinds such as those of watermelons.

Kuon shares a connection with Ioneos, a larger, similar entity occasionally described as its older brother. Both originate from an identical magical or crystalline substance. As the narrative reaches its conclusion, Kuon and Ioneos undergo a transformation: they enter dormancy, dissolve into mud, and solidify into a single, unified crystal. Owing to their inherent size disparity, Kuon emerges as a smaller fragment within this crystalline formation.