Lily Hoshino investigates for the Royal Police force in Cremona. Her sharp investigative skills stand in contrast to an outward demeanor often appearing immature, unprofessional, and scatterbrained, bordering on childlike. Nevertheless, she takes her duties seriously when required, possessing latent talent and intelligence considered comparable to the legendary investigator Keith Kazama Flick. Her personality features a notable enthusiasm for food, especially red bean buns, and an active enjoyment of techno music.

During the events of the ONA series, she participates in Royal Police operations to protect a significant politician linked to the Regies, an organization holding critical information sought by authorities. This role thrusts her into complex security scenarios involving supernatural threats and political intrigue, where her actions contribute to the team's efforts to maintain stability against emerging dangers targeting key figures.

Her interactions with colleagues reflect a professional dynamic centered on solving cases, though her occasionally rash behavior provides a counterpoint to her demonstrated deductive abilities during investigations. She operates within law enforcement responses to serial crimes and organizational conspiracies affecting the archipelagic nation.