Honoka Kurosaki is a middle school student one grade above Kokona Aoba, attending a local high school in Takasaki. She first appears during the Mount Tanigawa climb in the second season when Aoi Yukimura encounters her on the trail. Initially quiet and reserved, she carries a camera and expresses strong passion for photography, frequently capturing landscapes and hiking moments. Her reserved nature contrasts with the main group's outgoing personalities, but she gradually integrates through shared outdoor activities.

Her background includes an older brother, Taiki Kurosaki, though specific family dynamics remain unexplored. Photography recurs as her defining trait, with photos noted for evoking warmth—especially those featuring Kokona. This shared appreciation for photography and nature builds their friendship, as Kokona openly expresses fondness for Honoka's work. Kokona's presence motivates Honoka to join group outings despite her shyness, deepening their bond in later seasons.

Character development unfolds across seasons and an OVA. In season three, she joins Aoi, Hinata, and Kokona at Gunma's Lockheart Castle, documenting experiences with cameras. This reinforces her group role and comfort in observational activities. Her reserved demeanor lessens as she proactively engages in group interactions, accepting hike invitations even without Kokona.

During "Next Summit," a Valentine's Day hike to Mount Mitake sees Aoi and Hinata creating opportunities for Honoka and Kokona to connect. They visit "power spots" tied to relationship luck, including holding hands while passing between tree trunks—symbolizing their strengthening bond. Honoka reveals that a Lockheart Castle photo of Kokona emitted palpable warmth, deepening her desire to know Kokona better. Kokona reciprocates with admiration for Honoka's photography.

Later in "Next Summit," she joins a snowshoeing trip to Mount Akagi with Aoi, Hinata, and Koharu Senjuin. Despite unseasonable warmth melting most snow, she embraces the experience, showing increased group engagement. The outing concludes with a communal meal, further integrating her socially.

Her observational skills surface during a second-season summer festival, where she overhears Aoi discussing a disagreement with Hinata. Through this, she discerns the depth of their friendship and witnesses their reconciliation after a trivial argument.