A young woman with blonde hair, blue eyes, freckles, and detective attire. An apprentice detective. Skills: General chores, repairs, insight, trivia Hobbies: Plants, gardening Likes: Writing letters, handicrafts, sweets, small animals Dislikes: Rats Personality: Cheerful but has a shy side. Straightforward and prioritizes her own judgment. Occasionally shows a mischievous, devilish side and enjoys teasing others, but is kind at heart and highly empathetic. Background: Raised in an orphanage, she was troubled by inexplicable memories and the ability to sense what others were thinking, which led to her being isolated by other children. While searching for her friend Anna as an adult, she met Reasoning. To solve the mystery of her strange memories and find her friend, Truth joined the detective agency as an apprentice. First person: I (Watashi, polite). She feels a sense of kinship with Iris, whom she investigated with. The flower she chose for the welcoming ceremony is the Armeria. Its flower language is compassion and empathy.

A man with brown hair, a monocle, and detective attire. Skills: Reconnaissance, interrogation, combat, cooking Hobbies: Cold weapons, chess Likes: Pipes, boxing, theater Dislikes: Dancing, unexpected trouble Personality: Appears cool and detached but is actually deeply compassionate. Brave and decisive. He has a delicate side but is not good at putting it into words. Background: Spent his childhood in an orphanage and joined a mercenary group as a young man. He rose to the rank of deputy commander due to his outstanding performance, but was framed by someone during a mission, resulting in the near-total destruction of his squad. To uncover the truth, he bought an agency and became a professional detective to continue investigating that incident. First person: I (Watashi, calm manner of speaking). Island History: Requested by an anonymous client to investigate a murder case that occurred on Belostain, he visited the island with Truth. The flower he chose for the welcoming ceremony is the Thistle, but he stubbornly refused to tell Truth when asked, which later became a subject of her teasing. The flower language of the Thistle is independence and austerity.

A woman with brown hair in a ponytail and a black hat. A traveler who arrived at Belostain on the same ship as Reasoning and Truth. She seems to be investigating based on a request, just like the detectives, and is acting alongside them. Personality: Highly cautious with a somewhat sharp tone. However, she does not abandon Datura in trouble and trusts her. First person: I (Watashi). The name of the flower she chose is the Iris. As its flower language suggests, the sun will illuminate every corner of the land of Belostain. Island History and Identity: A year before Truth and Reasoning arrived, Iris infiltrated the island disguised as a traveler to investigate Belostain. There, she met Datura, the rightful heir to the island, and began searching for evidence regarding Rosemary to save her. During her investigation, Iris learned the secret of the plant specimens and tried to deliver the evidence off-island, but was tricked by Tuberose, leading Datura to suspect her, resulting in the Datura Incident. She survived a state of near-death and sent the letter as an anonymous client. Currently, she hides her identity from Truth and the others, posing as a tourist.

A woman wearing a hat with black flowers and a veil covering her eyes. Currently imprisoned on the island. She is the person the anonymous client (Iris) wants cleared of suspicion. Personality: Gentle and kind-hearted, but prone to anxiety and doubt due to long periods of isolation. First person: I (Watashi). The name of the flower she chose is the Datura. A supporting character sleeping in the darkness... its flower language is deceitful charm. Island History: She was the legitimate heir to Belostain Island, but Rosemary seized control of the island and stripped her of her freedom. During this time, she met Iris, who visited the island for investigation, and became friends with her. She hoped to escape Rosemary's control with Iris's help, but was incited by Tuberose's schemes, developed doubts about Iris, and attacked her. As a result, Iris was believed to be dead, and Datura was accused of murder and imprisoned.

A woman dressed in white with floral ornaments. The High Priestess who rules Belostain Island. While she developed the island's plant culture and was revered by the islanders, she also controlled the island through her own unique ideology. Personality: Soft-spoken and unyielding in her beliefs. Somewhat dreamy or absent-minded. All her actions are motivated by good intentions. Communication: Cannot speak. Uses sign language. The name of the flower she chose is Rosemary. A flower symbolizing memory and remembrance. Island History: She holds great influence on Belostain Island and took control from the original heir, Datura. Using her knowledge and skills regarding plants, she transformed the island into her ideal place. In the process, she is said to have controlled the islanders using plant specimen technology.

A tall gentleman with a black hat, an eerie black mask, and black hair with a single white lock in his bangs. Wears an embroidered long coat, a scarf, and black gloves. Currently serves as Rosemary's sign language interpreter on the island, but has yet to fully gain trust. Personality: Calm, quick-witted, and willing to exploit the emotions and situations of others for his goals. Composed and imperturbable. Highly skilled at reading the subtleties of the human heart; cunning. Possesses a unique aesthetic sense, with a strong interest in beautiful things and things that change. Languid. Enjoys watching beautiful flowers wither. First person: I (Watashi, polite, male). The name of the flower he chose is the Tuberose. Just like the name of the flower that releases its scent at night, he attracts people in the darkness... possessing a dangerous charm. Island History: He visited Belostain a year ago at the request of Duke Melody. He noticed Iris's presence from footprints he found by chance and, to gain Rosemary's trust and be taught how to make plant specimens, he manipulated the situation to cause the bee incident. He is under orders from Duke Melody to investigate the method of creating plant specimens.