Lily has straight, shoulder-length black hair and brown eyes, reflecting her Asian heritage. She is left-handed, a trait occasionally highlighted during her work. While on duty, Lily typically wears the standard uniform of the Royal Investigative Services. During her time off, she opts for more casual clothing, showing a relaxed and approachable side outside of her professional role.

Lily is often described as immature, impulsive, and occasionally scatterbrained, sometimes giving the impression of a carefree child. However, beneath her playful exterior, she is an exceptionally skilled detective who approaches her work with seriousness when the situation demands it.

She has a strong love for food, particularly red bean buns, and rarely passes up an opportunity to eat. Despite her seemingly lighthearted behavior, Lily can be highly determined and focused when necessary. Her intelligence and natural aptitude for investigation are considered to rival those of Keith Kazama Flick. In her personal time, Lily enjoys listening to techno music.

Lily Hoshina was born into a family of luthiers and was raised alongside her younger brother by her parents. During her high school years, she dated a boy who was passionate about astronomy, and the two often spent time together at a planetarium near a church. However, their relationship eventually ended for reasons that remain unknown.

After graduating from high school, Lily enrolled in the police academy, where she met future colleagues Mario Luis Zurita and Brian Brandon. Upon completing her training, she joined the Royal Investigative Service (RIS) and was later recruited by Erik Toga to become part of his investigative team, alongside Mario and Brian. During this time, she also became acquainted with Koku, who began working at her family’s shop.

During the Killer B incidents, Lily’s team served as the primary group handling on-site investigations. At the beginning of the series, Lily is seen rushing to a crime scene after oversleeping and receiving an angry phone call. In her haste, she bumps into Koku, who had bought red bean buns for her, but she quickly races off to the scene after grabbing her RIS badge and some food.

At the crime scene, Lily tries to sneak under the police tape but is caught by Boris Meyer, who reprimands her for being late. Offering him a red bean bun as a peace offering, Boris reluctantly accepts while explaining the case details, eventually showing Lily a tree marked with Killer B’s symbol. While processing the information, Lily notices a suspicious man at the scene. After confronting him, she learns he is Keith Kazama Flick, a former RIS agent welcomed by Boris but unfamiliar to her.

Later at headquarters, during a briefing, Erik formally introduces Keith to the team and reviews the morning’s case. Although the team discusses Killer B’s suspected involvement, Lily focuses on sketching Killer B’s symbol, trying to uncover its meaning.

Later that day, the squad is alerted to a stolen military IFV wreaking havoc on the main road toward the city. Lily and Boris are ordered to pursue the vehicle. During the high-speed chase, Lily, in typical reckless fashion, races through a park to intercept the IFV. Though she manages to catch up, the IFV retaliates with gunfire, forcing her to retreat. Despite coordinating efforts with Mario to trap the vehicle, the IFV escapes through a hidden passage in a tunnel.

Following orders, Lily and Boris proceed to the Museum of Flight near Mt. Ulm. Upon arrival, they find the IFV abandoned. As dawn breaks, Lily helps survey the crash site alongside forensic teams. Despite the army’s decision to close the case to avoid public scrutiny, Lily remains suspicious of the circumstances. The discovery of a satellite image showing that Killer B intentionally derailed a train to create his signature mark shocks Lily and her colleagues, deepening the mystery surrounding the case.

Koku / Killer B
Lily and Koku share a close friendship, developed through their connection at her family’s violin repair shop where Koku works. Lily treats Koku much like a younger brother and even jokes about setting him up with one of her friends. Initially unaware of Koku’s secret identity as Killer B, Lily remains oblivious until Episode 9, when she witnesses his transformation for the first time. After Keith explains Koku’s situation, Lily offers her support. Once the case concludes, their friendship returns to normal, with Lily also becoming affectionate toward Koku’s partner, Yuna.

Keith Kazama Flick
Throughout most of the series, Keith maintains a certain distance from Lily due to her resemblance to his late younger sister, Erika. Lily initially perceives Keith as strange but gradually comes to realize that they share many similarities. She resents being compared to Erika and finds Keith’s protectiveness and irritation frustrating. Despite their frequent clashes, Keith comes to respect Lily’s abilities, though he continues to view her as impulsive. Following the resolution of Erika’s case, Lily and Keith officially become partners, even as their bickering dynamic persists.

Boris Meyer
Boris serves as Lily’s superior at the Royal Investigative Services and treats her with a protective, fatherly attitude. In return, Lily regards Boris as a father figure. Despite their close bond, Boris often expresses frustration over Lily’s reckless driving habits, which frequently cause him concern.