Haruka Neya is a twenty-seven-year-old private investigator who specializes in a unique and delicate field known as separation operations, or breakup missions. Her professional background is rooted at the Kusanagi Detective Agency, where she once worked as a junior colleague to Sōsuke Kaburaya. During her early days as an investigator, her striking appearance proved to be a hindrance, causing her to fail at standard surveillance tasks. It was through the guidance and support of Sōsuke Kaburaya that she was able to find her professional footing, eventually discovering her true calling in the art of the honey trap.

Now an expert in her field, Haruka is renowned for her abilities as a breakup agent. Her method relies on a combination of refined seduction techniques and convincing acting skills, which she uses to make her targets believe she is genuinely interested in them. Her success rate is exceptionally high; she can charm even the most serious or romantically inexperienced men into following her to a hotel in a very short amount of time. Despite the assumptions of her colleagues who view her as promiscuous, Haruka operates with a strict personal code of conduct. On most assignments, after securing the target in a hotel room, she will attempt to persuade them not to commit infidelity. If this fails, she uses a sleeping pill to render them unconscious, allowing her to collect the necessary evidence and leave the scene without engaging in sexual relations. She has been known to state that such intimate acts occur only when she personally feels like it, reinforcing her commitment to her own boundaries.

Physically, Haruka is exceptionally attractive and takes great pride in her appearance, making her the center of attention wherever she goes. Her most notable features include bright, expressive red eyes and lustrous black hair that falls to her shoulders. Her personality is defined by a strong sense of confidence and professional pride, which was shaped by her academic and early career successes. While she projects an image of a charming and flirtatious woman, she is deeply serious about her work and protective of her reputation as a skilled professional rather than a frivolous person.

The most significant relationship in Haruka's life is with her former senior, Sōsuke Kaburaya. Her feelings for him are complex, blending admiration, professional respect, and a competitive jealousy, as she aims to surpass him in areas where he lacks expertise. Her initial goal was to make him fall for her using her refined seductive skills. However, as she persistently tries to gain his attention and affection, often to no avail due to his apparent indifference, she gradually develops genuine romantic feelings for him without fully realizing it. Even after Sōsuke left the agency to start his own practice, Haruka continues to collaborate with him, frequently visiting his office to introduce new cases and maintain their connection. She is also on good terms with Brenda Aisaki, whom she works with professionally, though they are also rivals in love due to their mutual affection for Sōsuke.

Haruka Neya serves as a supporting character whose role brings a specific professional expertise to the narrative. Her development is showcased through her journey from a struggling novice detective to a top earner and the star separation agent at her agency, all while navigating a deeply personal and unrequited love for her former mentor. The internal conflict between her professional confidence and her personal vulnerabilities, particularly when facing her true feelings for Sōsuke, is a central aspect of her character.