Suzune Horikita is a young girl with long black hair, typically styled with a single braid tied with a pink bow, and gradient red eyes that give her a striking appearance. She is often seen with a stern and serious expression, which complements her reserved and composed personality. Despite her cold demeanor, she is widely regarded as beautiful, attracting the attention of classmates such as Ken Sudō and Kakeru Ryūen due to her slim yet well-proportioned figure.

She typically wears the standard school uniform of Advanced Nurturing High School. Outside of school, her wardrobe varies depending on the occasion. She has been seen wearing a striped sundress and a sun hat, reflecting a more casual and elegant style. During the school’s survival test, she wore a red tracksuit, and she was also seen in a white bikini while at the pool.

In Volume 11.5, Suzune undergoes a significant change by cutting her hair short as a symbolic gesture of her determination to stop following in her brother’s footsteps. Previously, Manabu Horikita had told her that he liked her hair long and encouraged her to keep it that way, making her decision to cut it a defining moment in her character development. While her new hairstyle surprised her classmates, some, including Sudō, still found her charming.

Suzune Horikita is a serious and highly intelligent individual who rarely expresses emotion, maintaining a calm and composed exterior even in tense situations. Her stoic nature is evident when she remains unfazed after being threatened by a student from Class 1-C. However, her cold and distant demeanor often isolates her from her classmates, as she actively distances herself and looks down on others, believing that personal connections would only hinder her academic progress. She is blunt and straightforward, openly admitting that she has no friends because she views them as unnecessary distractions. Over time, however, her perception of relationships and teamwork begins to change.

Suzune initially exhibits an antisocial outlook, rarely speaking to anyone except Kiyotaka Ayanokōji upon their first meeting and refusing to trust others, especially those who attempt to befriend her, such as Kikyō Kushida. Unlike Kiyotaka, who is indifferent but open to friendships, Suzune actively disregards them, solely focusing on achieving promotion to Class A. Both Kiyotaka and her older brother, Manabu Horikita, suggest that her inability to cooperate with others and her single-minded determination toward her goal were key factors in her placement in Class 1-D.

Despite being highly determined, Suzune is also stubborn and resistant to change. She initially refuses to accept her placement in Class D, setting the seemingly impossible goal of rising to Class A, a feat never achieved in the school’s history. However, Manabu harshly criticizes her lack of self-awareness, stating that her weaknesses particularly her inability to work with others are holding her back. Suzune rejects the notion that friendships are necessary for success, though she does persuade Kiyotaka to assist her in achieving her goals. When he points out that her isolation from others may be the reason she was placed in Class D, she denies it, though she later briefly considers it as a possibility.

While Suzune maintains a composed attitude in most situations, her deep-seated fear of her older brother is a notable exception. She both admires and feels inferior to Manabu, struggling under the weight of his expectations. This is demonstrated when she visibly shakes in fear during a private meeting with him in Episode 2, when he nearly attacks her. A similar reaction occurs in Episode 5, where she is unable to speak during Ken Sudō’s hearing, only recovering after Kiyotaka intervenes.

Despite her outwardly cold and calculating nature, Suzune demonstrates moments of genuine kindness. A notable example occurs when she sacrifices 50,000 points to prevent Sudō from being expelled after he fails a test. Though she insists that she did so to further her own goals, her previous attempts to help him study suggest a more compassionate motive. Later, she actively defends Sudō during a disciplinary case, criticizing him but also firmly asserting his innocence.

As the series progresses, Suzune slowly becomes more open to trusting others. In Episode 7, she is seen smiling after reading an email from Kiyotaka, marking a shift in her usually stoic demeanor. She also entrusts Kiyotaka with guarding the boys’ tent during the uninhabited island survival exam, stating that she couldn’t fully trust Yōsuke Hirata alone. This trust in Kiyotaka deepens when she falls ill during the exam and relies on him to handle the situation in her absence.

Suzune’s character growth becomes most evident during the final days of the survival test. She realizes the hypocrisy of her initial views regarding Class D, recognizing that she had been acting similarly to the selfish and manipulative members of Class C. After being defeated by Mio Ibuki and later rescued by Kiyotaka, Suzune finally admits that she needs allies to succeed. Once the survival test concludes, she thanks Kiyotaka for helping her gain Class D’s trust, a rare display of gratitude. In the anime adaptation, this moment is particularly significant, as she appears flustered and shy, struggling to maintain eye contact while expressing her appreciation—an uncharacteristically vulnerable moment for her.

Since grade school, Suzune Horikita has consistently been a top-performing student, excelling in academics and maintaining an exemplary record. Throughout her three years of middle school, she was never tardy or absent, further cementing her status as a model student. It is noted that she attended the same middle school as Kikyō Kushida, though their relationship prior to high school remains largely unknown.

Suzune’s primary motivation for enrolling in Advanced Nurturing High School was to earn the recognition and approval of her older brother, Manabu Horikita, the highly respected Student Council President at the time. However, upon being placed in Class 1-D, the lowest-ranked class in the school’s hierarchy, she was shunned and humiliated by Manabu, who dismissed her as unworthy of his acknowledgment. His harsh treatment only strengthened her resolve to climb the school’s ranks and reach Class A, proving her capabilities to both her brother and herself.

Despite being assigned to Class D, Suzune is a highly capable student, possessing academic and athletic abilities comparable to those in higher-ranked classes. However, her greatest weakness is her antisocial nature and elitist mindset, believing that others would only hold her back. Her supercilious attitude and tendency to patronize others alienated her classmates, causing them to harbor resentment toward her. As a result, she remained a loner for nine years, failing to recognize the flaws in her approach.

It was not until she entered Advanced Nurturing High School that she slowly began to change. Over time, she formed alliances and valuable acquaintances, though she remained reluctant to consider any of them true friends with the exception of one person, who ultimately broke through her emotional barriers.

Suzune Horikita possesses exceptional overall abilities, excelling in both academics and physical performance. However, while she is highly competent, she is not without her weaknesses, particularly in areas that require social adaptability and strategic foresight.

Academic Abilities
Suzune is a dedicated and diligent student, spending much of her time studying due to her singular focus on reaching Class A. She strongly believes that she deserved to be placed in Class A from the beginning, given her high academic standing, and hopes that achieving this goal will finally earn her acknowledgment from her brother, Manabu Horikita.

Her academic prowess is best demonstrated in the Paper Shuffle special exam, where she successfully defeated Kikyō Kushida in a Mathematics exam, a subject that Kushida herself had chosen as the deciding factor in their bet. Suzune scored at least 98 points, while Kushida scored around 80, proving her superiority in the subject.

However, while highly capable, Suzune’s academic abilities do not match those of students from the White Room, as seen when Kiyotaka Ayanokōji effortlessly defeated her in another Mathematics exam, scoring a perfect 100 while she fell short. This highlights that while Suzune excels within the standard high school curriculum, her knowledge does not extend beyond its limitations.

Intellectual Abilities
Suzune is widely regarded as an intelligent and capable student. According to Sae Chabashira, she ranked third among all first-year students in the entrance exams, further proving her academic excellence. Honami Ichinose, a top student from Class 1-B, also acknowledged Suzune as one of the few Class D students worth keeping an eye on, recognizing her potential.

Despite her intellectual capabilities, her condescending attitude and lack of social awareness leave her vulnerable to manipulation and attacks from rival classes. She frequently underestimates the importance of forming alliances, choosing to interact with others only as a means to achieve her personal goals. Due to this weakness, she has been saved multiple times by Kiyotaka, whose strategic interventions prevented her from suffering defeats at the hands of her rivals.

Physical Abilities
Suzune also possesses strong athletic and combat skills, making her a well-rounded student. She has been noted to be an above-average swimmer, as revealed during a conversation with Kikyō Kushida at the school pool. Additionally, during Ken Sudō’s disciplinary hearing, she mentioned having experience in martial arts, though the full extent of her training remains unknown.

Her proficiency in grappling techniques is evident when she effortlessly flipped Haruki Yamauchi without any difficulty, showcasing her strength and technique. Suzune’s combat abilities were further highlighted in her fight against Mio Ibuki, where she initially held her own and even earned praise from her opponent before ultimately being knocked down due to illness.

While skilled in combat, Suzune is not among the strongest fighters in the school. This was evident when she faced Ichika Amasawa, an injured and fatigued opponent, yet was still easily defeated, demonstrating that while competent, she is not on the same level as the most elite fighters within Advanced Nurturing High School.

The name Suzune (鈴音) is composed of the kanji 鈴 (suzu), meaning “bell,” and 音 (ne), meaning “sound.” This could symbolize clarity, resonance, or a presence that rings through, reflecting her sharp intellect and strong will.

Her surname, Horikita (堀北), is made up of the kanji 堀 (hori), meaning “moat”, and 北 (kita), meaning “north.” This combination may imply a guarded or defensive nature, which aligns with Suzune’s initially distant and reserved personality, as well as her struggle to break down emotional barriers.