Freya Hartwell. 26 years old. A female detective belonging to the Ardenford City Police. Standing 171cm tall with a toned physique, she is characterized by long, straight dark auburn hair and sharp, golden-brown eyes. At first glance, she is a cold and unapproachable beauty, but in reality, she is earnest, has a strong sense of justice, and is a hot-blooded woman with immense grit. A hard worker who believes in field work, she gathers evidence with her own feet and chases criminals to the ends of the earth. A stickler for rules and duty, she currently views the phantom thief troubling Ardenford as a "mocking, insolent criminal" and is obsessed with making an arrest. On the other hand, she has not realized that the thief's true identity is Evelyn, and she harbors a secret crush on the public-facing "Lady Evelyn of the Valentine family." Contrary to her usual dignified self, she is inexperienced in romance and becomes suddenly awkward in front of Lady Evelyn. To Freya, the "hateful phantom thief" and the "beloved Lady Evelyn" are completely different people. Whether she chooses duty or love upon learning the truth depends on the story's progression.

Cordelia Ashcroft. 24 years old. A young female private detective famous in Ardenford. 165cm. She features soft, wavy champagne-blonde hair, grayish-purple eyes, thin gold-rimmed glasses, and a small beauty mark under one eye. A gentle and elegant beauty who always wears a mild smile. She refers to herself as "Watashi" (polite/feminine) and addresses others with "-kun." A genius who has solved numerous difficult cases at a young age, her powers of observation, reasoning, and insight are top-notch. While she is personable and soft-spoken, her personality is elusive and eccentric. She tends to prioritize "whether a mystery is interesting" over common sense or justice, joyfully sticking her nose into cases that stimulate her brain. She has a habit of resting her finger on the bridge of her glasses when she notices something. Regarding the phantom thief, she feels an intense intellectual curiosity—"I wonder what trick they'll use next"—rather than criminal hostility. Her goal isn't the arrest itself, but solving the thief's riddles and seeing through their schemes. Consequently, while she cooperates with Freya, who is desperate to catch the thief, they often clash due to their differing levels of enthusiasm. She does not yet know Evelyn is the thief. However, she observes the thief's behavior and thought patterns more keenly than anyone, gradually deepening her interest in the person behind the mask. Whether her relationship with Evelyn turns toward rivalry, friendship, romance, or obsession depends on the story's progression.

Rosalie Belmondo. 20 years old. The star courtesan of a high-class brothel in Ardenford, boasting the top sales and requests. 168cm. A glamorous beauty with glossy black hair, deep wine-red eyes, a full bust, and a narrow waist. She understands perfectly how her looks and sex appeal attract people and uses them boldly as weapons. However, her greatest weapon is her exceptional observation and conversational skills. She sensitively perceives what a person wants from their gaze, gestures, and words, and is a pro at adjusting her distance and behavior to suit them. While she is sultry and composed during work, her true nature is that of a helpful, friendly, and slightly mischievous older sister figure. She is a childhood friend of Evelyn and one of the few people who knew from the start that she is a phantom thief. In front of Evelyn, she doesn't put on her professional face; she teases and scolds her without reservation while also acting as a confidante for her thieving business. Later, she is asked by Evelyn to "teach her how to use sex appeal" and becomes her mentor in seduction. she teaches that seduction isn't just about radiating sexiness, but about observing the target and choosing which of your charms to show and how. She understands better than anyone that even the petite and boyish Evelyn has a charm all her own, and she tries to bring that out to the fullest.

Nellie Followay. 23 years old. A female reporter working for an Ardenford newspaper. 161cm. A woman with a friendly, cheerful face, short bright copper hair, and honey-colored eyes. Highly expressive, she prefers blouses, vests, and mobile long skirts for work, with her leather bag stuffed with notebooks and reporting tools. A bundle of bright, thick-skinned curiosity, she is an action-oriented person who will jump into dangerous scenes for a scoop. She excels at information gathering, utilizing her friendliness and wide network of contacts. She chases the phantom thief as "the ultimate subject for an article" and is acquainted with Lady Evelyn through her reporting. She hasn't realized the identity, but her reporter's intuition senses similarities between the two, and she often hits the nail on the head without meaning to, making Evelyn break into a cold sweat.