Kodaka is of mixed heritage, being half-British, which is most evident in his dirty-blond hair inherited from his late mother. In contrast, his facial features resemble his father’s, giving him a distinctly Japanese appearance that conceals his foreign lineage. His dark-gray eyes and sharp expressions often cause others to perceive him as intimidating and unapproachable, despite his actual personality.

Due to his appearance, Kodaka frequently comes across as stern or angry even when unintentionally which contributes to his reputation as a delinquent. This misunderstanding often causes other students to avoid him, though Kodaka is aware of the effect and occasionally takes advantage of it when necessary.

His typical attire is the St. Chronica’s Academy uniform, though he personalizes it by rolling up his pants. Outside of school, he dresses casually, usually wearing a T-shirt and medium-length pants. A consistent accessory throughout the series is the necklace he wears around his neck, a personal item that adds to his distinct look.

Despite his intimidating appearance, Kodaka is a calm, patient, and kind-hearted individual. He generally speaks softly, maintains a polite attitude, and avoids resorting to violence unless absolutely necessary. His intimidating expression often leads to misunderstandings, causing others to mistake him for a delinquent, though he occasionally leverages this reputation to protect others by scaring away aggressors.

Kodaka has a strong desire to form friendships, which is the main reason he joins the Neighbors Club. This longing is reflected in moments such as his satisfaction with befriending a male character in a dating simulation game, despite reaching a “bad ending” with the heroines. However, his attempts to make real-life friends often backfire because his intimidating look frightens people before he can express his genuine intentions.

Among his notable traits is his patience and self-control. He rarely loses his temper, even when insulted, and takes on the role of mediator within the Neighbors Club. He does not hesitate to scold others when necessary, such as reprimanding Sena Kashiwazaki for arrogance, while still showing fairness by blaming her tormentors when she is bullied.

Kodaka’s interactions with his clubmates are a blend of sincerity and restraint. He treasures the Neighbors Club deeply, regarding it as his source of happiness, but he hesitates to acknowledge the group as true friends out of fear that change might disrupt their fragile bonds. His reluctance to address romantic feelings directed toward him also stems from this fear, often leading him to invite multiple members to group outings instead of accepting individual “dates.” While he sometimes makes heartfelt remarks such as comparing Rika Shiguma to a “wildflower blooming on a hill” he often frames them as slips of the tongue, avoiding responsibility for his own emotions.

Over time, Kodaka becomes more open to recognizing others’ feelings. After bonding with Rika, he admits that he had been ignoring and deceiving himself to avoid change, a flaw he gradually begins to confront. Despite his embarrassment in handling romantic tension, he shows more willingness to acknowledge the affection his friends have for him.

In addition to his kindness, Kodaka has a quirky sense of humor that others often fail to appreciate. He confidently delivers jokes and fabricated stories that typically fall flat with his clubmates, though Maria Takayama sometimes enjoys them. His persistence in sharing this humor, even when it goes unappreciated, reflects both his resilience and his awkward charm.

Outside of social interactions, Kodaka is fond of reading shōnen manga, reflecting his interest in adventurous and youthful themes.

Intelligence
Kodaka is academically above average, with English being one of his strongest subjects, reflecting his half-British heritage. Within the Neighbors Club, he is often regarded as the voice of reason, attempting to ground his eccentric peers in reality. Despite this, Kodaka is not particularly skilled with modern technology, as shown by his lack of awareness of his cell phone’s functions or his struggles with console gaming.

Although he appears romantically oblivious, it is revealed that Kodaka deliberately pretends not to notice the feelings of others in order to avoid conflict and maintain harmony within the club. His ability to reason and defuse situations highlights his quick thinking, though characters such as Rika Shiguma see through his attempts at feigned ignorance.

Physical Prowess
Years of bullying and isolation due to his appearance hardened Kodaka both mentally and physically. In the light novels, he states that he is capable of fending off multiple attackers at once, though he prefers to avoid violence whenever possible. He has shown considerable stamina, able to carry multiple heavy bags and walk long distances without tiring.

Domestic Abilities
With both parents largely absent, Kodaka took on the role of caretaker in his household, particularly for his younger sister Kobato. He is highly skilled in domestic tasks such as cooking and cleaning, and is noted for preparing non-traditional dishes, including paella. His passion for cooking is strong enough that he is often engrossed in studying kitchenware while shopping.

Other Skills
Kodaka is a competent swimmer, skilled enough to teach Sena how to swim, though he admits that Kobato surpasses him in ability. He is also able to fish, a talent revealed in the anime adaptation. Additionally, Kodaka takes pride in telling jokes and scary stories, though most of his humor is appreciated only by Maria, leaving his other friends unimpressed.

Yozora Mikazuki
Yozora is Kodaka’s childhood friend, though he initially fails to recognize her when they reunite at St. Chronica’s Academy. Yozora identifies him immediately but chooses not to reveal their past connection until much later. Kodaka is often surprised by Yozora’s tendency to ridicule others, yet their history allows them to remain close. Despite this bond, Kodaka acknowledges that their childhood friendship no longer defines their relationship, viewing Yozora primarily as a fellow member of the Neighbors Club rather than as his “best friend.”

Sena Kashiwazaki
At first, Sena perceives Kodaka as another boy who might be interested in her beauty and status, often mocking his hair and “yankee-like” appearance. However, her view of him changes when Kodaka resists her offers of being stepped on or mistreated as a “reward,” behavior that sets him apart from her other male classmates. After Kodaka reprimands her for arrogance something no boy had ever dared to do, Sena begins to respect him and eventually develops romantic feelings toward him.

Yukimura Kusunoki
When Kodaka first meets Yukimura, he suspects that she is female, though Yukimura insists she is male in her pursuit of becoming more “manly.” Misled by Yozora, Yukimura becomes Kodaka’s self-proclaimed servant, carrying out his requests with extreme devotion. Kodaka, however, tries to discourage Yukimura’s idealized image of him as a rough and rebellious role model, though her persistent self-deprecation leaves him little choice but to tolerate her behavior.

Rika Shiguma
Kodaka is frequently uncomfortable with Rika’s flirtatious comments and overt perversion, though he occasionally admits that under certain circumstances she falls within his “strike zone.” Among all the members of the Neighbors Club, Rika understands Kodaka’s feelings the best, particularly his reluctance to confront the romantic affections directed at him. She directly challenges him on this issue, though she ultimately respects his decision to prioritize friendship over romance. Kodaka also recognizes Rika as his first genuine high school friend and appreciates her efforts behind the scenes to make the Neighbors Club a more welcoming and enjoyable place.

The given name Kodaka (小鷹) is written with the kanji for “small” (小, ko) and “hawk” (鷹, taka), which can be interpreted as “little hawk.” This may symbolize his misunderstood image, appearing fierce or intimidating like a hawk, while in reality being gentle and thoughtful.

His surname Hasegawa (羽瀬川) is composed of the characters “feather” (羽, hane), “rapids” (瀬, se), and “river” (川, gawa), evoking imagery of flowing water and flight. Taken together, his full name blends avian and natural motifs, possibly reflecting both his mixed heritage and the contrast between how others perceive him and who he truly is.