Hina Tsurugi moved from Tokyo to her family's coastal hometown in Ashikita, Kumamoto, planning to focus on indoor hobbies like arts and crafts. Her intentions shifted after meeting third-year student Yūki Kuroiwa, who recruited her into the Breakwater Club when an octopus landed on Hina during their first encounter.

Hina consistently described herself as an indoor-oriented person, displaying strong preferences for knitting and needle felting alongside pronounced aversions to insects and creatures she deemed "gross," especially certain marine species during fishing. Her personality blended curiosity and stubborn persistence, occasionally aiding her fishing efforts despite impatience hindering progress. Tangled fishing lines triggered a compulsive need to untangle them for mental relief, and she frequently used needle felting to ease nervousness.

Through club activities, she gradually adapted to fishing despite initial reluctance. Early challenges included physical exhaustion from the club’s location, struggles with casting techniques, and visceral reactions to handling marine life like descaling fish. She overcame hurdles such as catching her first flathead through persistent effort and lure instruction, though processing the fish caused distress. Experiences like clamming and squid fishing tested her comfort zones, with protective gear reducing discomforts like ink exposure.

A pivotal moment followed failed whiting fishing with artificial bait; independent research on fish behavior led her to adjust techniques and succeed, demonstrating growing problem-solving initiative. Perseverance evolved through repeated failures like losing bait or catching seaweed, cultivating deeper appreciation for fishing’s process and outcomes. She reconciled crafting skills with club activities by creating matching plushies with childhood friend Natsumi Hodaka and teaching needle felting to other members.

Relationships within the Breakwater Club shaped her journey. Yūki served as both recruiter and persistent encourager, often convincing Hina to extend fishing sessions or try new methods. Natsumi’s enthusiasm provided relatable peer engagement, while second-year member Makoto Ohno offered reliable technical guidance during fishing and fish preparation. Her father, a former club member, facilitated participation through his stored fishing gear.

Hina’s background included a nearly forgotten childhood bond with Natsumi, whose club presence weakened Hina’s initial resolve to quit. Her character arc concluded with balanced appreciation for fishing’s rewards and the club’s social dynamics, contrasting her solitary crafting interests with collaborative outdoor joy.