Higuchi is a petite, young woman with shoulder-length blonde hair, often styled in a messy bun. Her deep brown eyes give her a striking appearance, although she typically conceals them behind rectangular blue sunglasses. She is most commonly seen wearing a black suit, which she leaves unbuttoned for a casual yet professional look.

When attempting to deceive members of the Armed Detective Agency, Higuchi adopts a more polished appearance. In these instances, her hair is neatly brushed and left down, her sunglasses are absent, and her jacket and shirt are properly buttoned, enhancing her refined presentation.

After being bitten by Ryūnosuke Akutagawa, Higuchi undergoes a transformation into a vampire. In this vampiric form, her eyes turn entirely black with no visible pupils, and her hair becomes significantly messier, reflecting her altered, menacing state.

As a mafioso, Higuchi demonstrates ruthlessness and a fearsome determination, showing no hesitation in eliminating her targets. When facing adversaries, she maintains a cold and professional attitude, rarely displaying empathy and taking swift action to enforce Port Mafia’s dominance. She has little patience for disrespect and despises those who underestimate the Mafia’s power.

However, Higuchi’s underlying personality is less suited to the harsh world of the Mafia. Beneath her tough exterior, she is sensitive, easily shaken, and prone to self-doubt. Her hesitancy and uncertainty about her role in the organization have led her to consider leaving the Mafia on multiple occasions, though she remains due to the challenges and dangers that defection would entail. Her subordinates often fail to respect her, following her orders primarily out of fear of Akutagawa’s retaliation rather than personal regard. Higuchi’s impulsive tendencies sometimes lead her to take drastic actions, occasionally clashing with directives.

Despite these vulnerabilities, Higuchi’s sincerity and determination earn her a degree of respect among the Black Lizard members. She is reliable and courageous, willing to face danger head-on, even if her decisions can be clouded under pressure. She strives to carry out her responsibilities and avoids unnecessary cruelty, maintaining a professional demeanor in service to both Akutagawa and the Port Mafia. Her decision to share critical information with Akutagawa played a pivotal role in luring him to the Guild’s Moby Dick, showcasing her loyalty and resolve.

Higuchi’s emotional stability fluctuates—at times she can be composed and intimidating, while in other moments she is visibly unsettled or stressed. She is better suited to covert operations, as her tendency to panic can leave her vulnerable in direct confrontations.

Her most significant weakness lies in her unwavering, almost obsessive loyalty to Ryunosuke Akutagawa. Higuchi prioritizes his well-being, often volunteering to take on his tasks out of concern for his frail health. This loyalty is frequently met with harsh and dismissive treatment from Akutagawa, who considers her efforts unnecessary. Despite his abusive behavior, Higuchi continues to remain steadfastly devoted to him, willing to endure any hardship for his sake.

The specific reasons behind Higuchi’s decision to join the Port Mafia remain unclear. Her motivations and circumstances prior to her affiliation with the organization have not been revealed. The only known detail about her personal life is that she lives with her younger sister, suggesting she has familial ties outside her role in the Mafia. Despite the secrecy surrounding her background, her actions and loyalty to the Mafia imply a strong commitment to her role within the organization.

Higuchi’s ability remains unidentified, leaving its nature and potential applications a mystery. Despite this, she compensates with exceptional firearm proficiency, showcasing impressive combat skills. She frequently wields pistols and submachine guns with remarkable precision and efficiency, often relying solely on her firearms to eliminate groups of adversaries with ease. Her expertise in gunplay solidifies her role as a capable and formidable mafioso within the Port Mafia.

Higuchi’s primary role in the series is as Akutagawa’s assistant, ensuring his orders are carried out efficiently and providing support during missions. Her loyalty to Akutagawa is unwavering, even when his harsh demeanor makes her tasks difficult.

While Higuchi is not an ability user, she is proficient with firearms and often provides backup during battles. Her resourcefulness and quick thinking make her a valuable asset in combat, even against powerful ability users.

Higuchi’s human side and occasional insecurities set her apart from other mafiosos. Her internal struggle between loyalty to the Port Mafia and her personal morality adds depth to her character, offering a more nuanced view of life within the organization.

Ichiyō Higuchi represents themes of loyalty, perseverance, and humanity within the violent world of the Port Mafia. Her struggles to balance duty with her personal morality, as well as her dedication to Akutagawa, make her a relatable and multidimensional character in Bungo Stray Dogs. Higuchi’s resourcefulness and unwavering determination ensure her place as a memorable figure in the series.