Horikita Suzune

Biodata

Feature	Details
Name	Horikita Suzune (堀北鈴音)
Species/Race	Human
Gender	Female
Affiliation	Advanced Nurturing High School; Class D, later Class A 146
Occupation/Role	Student; Black Sphere participant; Su Wei's swordsmanship student; Mysterious Merchant
Status	Alive 229
First Appearance	Chapter 1

Power Progression

Stage / Realm / Level	Chapter	Notes
Black Sphere participant	17	Finished her first documented trial with 2 S Points; the Black Sphere judged her as ambitious but unable to secure major results.
Reinforcement Suit user	92	Entered a duel against Su Wei wearing a Reinforcement Suit, but learned its blue circular nodes can be punctured to disable its enhancement.
Swordsmanship apprentice	92	Accepted Su Wei as her teacher after being decisively defeated, then began daily sparring with Ichinose Honami.
Raiotrooper transformation	134	Transformed into Raiotrooper and slaughtered scattered monsters during a crisis.
Mysterious Merchant	165	Received examination-area death immunity and a 10% item-point commission, with an item removed from her stock for each fatal revival.
Ripple Qi Gong threshold	166	After initially struggling with Ripple because of self-doubt and emotional repression, she touched its threshold and planned to channel it through the Black Key.
Stand manifestation: Crazy Diamond	185	Accepted the Crazy Diamond Stand Disc; the Stand manifested despite seeming reluctant to cooperate with her personality.

Background / History

Horikita entered Advanced Nurturing High School as one of Class D's strongest academic students, ranking within the top five of her year on the entrance exam. Her exceptional results did not translate into social standing: she was cold, proud, and isolated from nearly all of her classmates. When Class D fell to zero points, she volunteered to recover the class's standing and declared that she would prove herself right through results. 8

Her first Black Sphere trial exposed the limits of that confidence. She initially rejected the X-GUN Su Wei offered her, but accepted after he pointed out that karate would not be enough against spirits. An Evil Spirit nearly reached her before Ichinose Honami shot it, forcing Horikita to confront her fear and dependence on others. She later sought temporary cooperation with Su Wei, gained one of the trial's kills, and finished with only 2 S Points. The poor result humiliated her, but she did not deny the evaluation. 11 12 13 17

After Class D mistakenly credited her with the trial's success, Horikita wanted to correct them rather than accept glory she had not earned. Su Wei stopped her, asking her to preserve the misunderstanding so he could avoid attention. She repaid the perceived favor by offering to tutor him, though her condescending delivery led him to criticize her interpersonal skills. 18 19

Her strained relationship with her older brother, Horikita Manabu, became a decisive source of pressure. Seeking old exam papers and Black Sphere intelligence from him, she tried to justify using every method permitted by the school's rules. Manabu dismissed her achievements as borrowed and told her to drop out; Horikita answered by resolving to rise to Class A, clear the Black Sphere exams, and become student council president through her own ability. 24 25

Her later experience in the Kabane trial showed a more practical side. She used a radar to locate enemies and trapped students, led her group through the school building, and pursued the hidden final boss rather than merely following stronger classmates. 28 31

When the Black Sphere exams became increasingly lethal, Horikita refused Su Wei's suggestion that she withdraw. He challenged her to prove herself in a duel, easily defeated her despite her Reinforcement Suit, and exposed the suit's weak points. Rather than retreat, Horikita discarded her pride, formally asked him to teach her strength, and began sword training alongside Ichinose. 91 92 95

After witnessing her brother vanish into a Black Sphere space during a battle with Jogo, Horikita was devastated but continued acting decisively. By the time she later saw Manabu alive again, she consciously refused to return to her old habit of blindly seeking his approval. 130 146 222

Appearance

Horikita is a student with long, straight black hair and a polished school-uniform appearance. Her usual posture—arms crossed, distant expression, and cold demeanor—makes others instinctively keep their distance. 8

• Long, straight black hair. 8
• Sharp, phoenix-like eyes. 18
• Often maintains a rigid, composed posture even under pressure. 11 91
• Wears a pitch-black Reinforcement Suit during combat and training. 92

Personality

At the beginning of the story, Horikita is intensely proud, competitive, and convinced that individual ability should determine a person's value. She struggles to express concern without sounding dismissive or patronizing, leaving her with little rapport in Class D. Even when attempting to help failing students, she initially frames assistance as an obligation rather than cooperation. 8 19 22

She is also deeply honest about achievement. Horikita resents accepting credit for Su Wei and Ichinose's contributions, feels genuine shame over her 2-point trial result, and refuses to rely on Su Wei's charity after Manabu challenges her worth. 17 18 24

Her drive to surpass Manabu becomes both her motivation and her weakness. She repeatedly risks herself to prove she is not weak, yet Su Wei identifies her perfectionism and suppression of emotion as the reasons she cannot initially master Ripple Qi Gong. 91 151

Over time, Horikita becomes more empathetic without losing her bluntness. She encourages Shiina Hiyori when Shiina admits fear of death, tutors struggling classmates despite refusing to indulge them with answer keys, and gives Nanase Tsubasa a marked-up Ripple manual and a place to train. 75 98 151

Abilities & Skills

Academic Ability and Analysis

Horikita is an elite student with strong logical reasoning and a methodical approach to problems.

• Ranked among the top five students in her year on the entrance exam. 8
• Prepared detailed study notes and practice materials for underperforming students. 22 97
• Calculated that crushing a regulation basketball required roughly 500–1,000 kilograms of instantaneous compressive force, excluding the resilience of its internal nylon winding. 38
• Recognized the viability of Shiina's strategy to lower the class average and protect students from the midterm elimination threshold. 97 98
• Identified Ayanokoji Kiyotaka as a potential Parasite based on his behavior, though she lacked authority to act without a Black Sphere mission. 23

Tactical Leadership

Horikita adapts quickly to changing trial conditions and is willing to take command when necessary.

• Proposed cooperation with Su Wei for the latter stages of her first Evil Spirit trial. 13
• Used a radar to identify enemy locations and a trapped student during the Kabane trial. 28
• Led her group toward the hidden final boss after prioritizing the group's route and objectives. 31
• Explained Black Sphere risks, equipment weaknesses, and Advance Test strategies to Nanase Tsubasa. 150

Swordsmanship and Close-Quarters Training

After accepting Su Wei as her teacher, Horikita began practical sword training with Ichinose as her regular sparring partner.

• Uses formal kendo strikes and calls, though Su Wei initially dismantled her textbook-perfect attacks with ease. 92
• Trains in Reinforcement Suit combat, concentration, and adapting to high-speed movement. 95
• Learns to recover from distractions and maintain a combat-focused state. 95 99
• Her early lack of practical combat experience remains a major limitation against superior fighters. 92 95

Reinforcement Suit

The Reinforcement Suit greatly boosts Horikita's physical strength and speed.

• Used its explosive force to launch high-speed kicks during her duel with Su Wei. 92
• Demonstrated its strength advantage to Nanase, overwhelming Nanase's trained martial-arts ability. 150
• Its blue energy rings are a critical weakness: puncturing them causes fluid leakage and removes the enhancement. 92 150

Ripple Qi Gong

Horikita studies Ripple as a life-energy technique effective against enemies vulnerable to light.

• Initially failed to properly awaken Ripple because her perfectionism and emotional restraint prevented her from reaching its required “flow.” 151
• Eventually touched the threshold of Ripple and intended to infuse it into the Black Key. 166
• Shared her annotated Ripple Qi Gong manual with Nanase to help her prepare for future trials. 151

Stand: Crazy Diamond

Horikita successfully accepted the Crazy Diamond Stand Disc.

• Crazy Diamond manifested behind her after the disc fused smoothly with her. 185
• Horikita sensed that the Stand disliked her personality but was still willing to lend her its power. 185
• She trained with Su Wei and Karuizawa Kei to use Stand possession for self-defense. 186

Equipment / Weapons / Items

• X-GUN — Given to her by Su Wei for her first Evil Spirit trial. 11
• Radar — Used to track Kabane and locate nearby survivors. 28
• Reinforcement Suit — Enhances physical ability but has vulnerable blue energy nodes. 92 150
• Wooden swords — Used during training and sparring with Su Wei and Ichinose. 92 95
• X-SHOT GUN — Used while observing the battle involving Horikita Manabu and Jogo. 130
• Black Key — A cross-shaped longsword with purification properties; vampire wounds caused by it cannot regenerate. 166
• Black Sphere Katana — Carried during later combat encounters. 218
• Ripple Qi Gong manual — Annotated copy she shared with Nanase. 151
• Crazy Diamond Stand Disc — Fused into her body and manifested as her Stand. 185

Relationships

• Su Wei — Initially a reluctant temporary ally. His decision to let Class D misattribute trial credit to her frustrates Horikita, but he later becomes her swordsmanship teacher, adviser, and the person whose judgment she trusts most. She eventually confesses her feelings to him alongside Karuizawa. 18 92 147 185
• Horikita Manabu — Her older brother and the central source of her desire to become stronger. His harsh criticism drives her to prove herself, though she later learns he had entrusted her safety to Su Wei. 24 90 91
• Ichinose Honami — Saved Horikita from an Evil Spirit during her first trial. Later becomes her regular sword-training partner and a fellow student of Su Wei. 12 95
• Karuizawa Kei — A fellow Class D student who eventually supports Horikita's confession to Su Wei. The two train alongside Su Wei after receiving Stand Discs. 185 186
• Nanase Tsubasa — A junior whom Horikita guides through Black Sphere dangers, Reinforcement Suit capabilities, and Ripple practice. 150 151
• Kushida Kikyo — Longstanding hostile classmate who knows Horikita's past and initially wants her removed from school. They later serve together as Mysterious Merchant and support staff. 68 165
• Shiina Hiyori — A fellow participant whose strategic academic idea Horikita supports; Horikita also reassures her that fear of death is normal. 97 98
• Matsushita Chiaki — Fought alongside Horikita against puppets and urged her to prioritize survival before mercy. 229
• Sakayanagi Arisu — An academic and Black Sphere rival with whom Horikita maintains tense, pragmatic cooperation. 14 28

Story Role / Major Arcs

• Class D's Zero-Point Crisis — Volunteers to represent Class D and reclaim its lost points. 8
• First Evil Spirit Trial — Confronts fear, receives Ichinose's rescue, cooperates with Su Wei, and earns 2 S Points. 11 12 17
• Manabu Confrontation — Attempts to secure old exam papers, is rejected by her brother, and resolves to earn success independently. 24 25
• Kabane Trial — Uses radar intelligence and takes a leadership role while pursuing the hidden boss. 28 31
• Su Wei's Apprenticeship — Loses a duel despite her Reinforcement Suit, recognizes her weakness, and begins swordsmanship training. 91 92 95
• Manabu's Disappearance — Witnesses her brother being swallowed by a Black Sphere space during the battle against Jogo. 130
• Nanase's Mentor — Demonstrates combat equipment, shares Ripple knowledge, and helps Nanase train. 150 151
• Mysterious Merchant Exam — Becomes the Mysterious Merchant, purchases a Black Key, and prepares to defend herself with Ripple. 165 166
• Stand Disc Trial — Manifests Crazy Diamond and trains in Stand possession. 185 186
• Puppet Battle — Balances her conscience against battlefield necessity, choosing neither indiscriminate killing nor reckless mercy. 229

Notable Quotes

“I will not rely on your charity! And I will never let you give me credit again! I will accomplish it with my own ability!” 24

“My life is mine to control, and my death... must also be decided by me!” 91

“Teacher! Please teach me how to become strong! Please make me strong enough... to endure everything!” 92