Su Lin

Biodata

Feature	Value
Name	Su Lin (苏林)
Alias(es)	X; Infinite Possibility, Fleeting Shadow (hero name) 33 163
Gender	Male main body; assumes female forms through his avatars 4 239
Affiliation	U.A. High School, Class 1-A; Demon Slayer Corps; Hero Association 9 101 240
Occupation/Role	Hero student, Class Representative, Demon Slayer Corps weaponsmith, hero 9 90 240
Status	Active 259
First Appearance	Chapter 1

Power Progression

Stage / Realm / Level	Chapter	Notes
Yukino training baseline	2	Yukino’s regeneration lets Su Lin use destructive training; her single-arm strength reaches 80 kilograms.
Mysterious Heroine X unlocked	3	Unlocks X’s Spirit Core Stage One, sword techniques, and Nameless Victory Sword A++; initial daily duration is five minutes.
Sister Doma unlocked	16	Gains a defensive/support avatar whose Rabbit Plushie transfers damage from Su Lin’s main body to her.
Takanashi Rikka unlocked	31	Gains Evil Eye, which increases physical fitness tenfold, and Chuunibyou, which can turn imagined effects into reality.
Kurotama unlocked	67	Gains Daily and Combat forms, extreme survivability, and the Imperial Armament Yatsufusa.
Main Body begins growth	75	The System enables the main body to train; initial recorded attributes are Strength 2, Spirit 2, Constitution 2, and Resistance 0.
Main Body combat growth	77	Attributes rise to Strength 5, Spirit 3, Physique 4, and Resistance 1; he can kill basic low-level demons alone.
Yatsufusa: Demon Slayer +6	90	Kurotama’s blade can decapitate Lower Rank demons at full power.
Yukino appointed Mist Pillar	101	The Demon Slayer Corps recognizes Yukino’s contributions and grants her a Pillar title.
Yatsufusa: Demon Slayer +15	103	Su Lin’s forging approaches intermediate level; further reinforcement becomes increasingly failure-prone.
Academy City Level 5	112 113	Kurotama is assessed as a Level 5 esper after enrolling at Tokiwadai Middle School.
Physical power increase	143	Su Lin’s punching force reaches 20 tons.
Mysterious Heroine X extension	155	X can maintain Spiritron Dress Phase 2 for 10 minutes, Phase 1 for 30 minutes, or a non-combat state for 8 hours; she may be summoned three times daily.
Putative Level 6	163	Academy City’s General Council considers classifying Su Lin’s strength as Level 6.
Kanade Tachibana unlocked	185	Completes the Combat Skill Training quest and receives a combat-type avatar.
Schubie and God Strike	213	Gains the Mechanized Race avatar Schubie; the main body receives one God Strike release opportunity.
One-Punch Man physical output	239	In Yukino form, Su Lin demonstrates 8,000 tons of muscle power, with estimated output exceeding 16,000 tons.

Background

Su Lin initially lives in poverty, supporting himself through part-time work while concealing his male main body behind the female avatar Yukino Yukinoshita. He can operate both bodies at once, such as cooking with his main body while Yukino knits clothing. His closest school friend, Torhu Hagakure, knows that he is male. 1 2

He identifies his Quirk as Clones: he can manifest separate bodies or transform directly into them, with each avatar possessing different abilities. Teachers initially dismiss the Quirk as cosmetic until he demonstrates Mysterious Heroine X’s sword strike. 4

Su Lin possesses foreknowledge of several worlds’ original storylines, but his interventions gradually alter events and make that knowledge less reliable. 4 9

Appearance

Su Lin’s main body is a handsome young man who commonly wears a black robe. His appearance changes completely when he assumes an avatar form. 2 4

• Yukino Yukinoshita — long black hair, dark eyes, plaid skirt, and black thigh-high socks. 1
• Mysterious Heroine X — a blonde swordswoman in a dark uniform and hat, wielding a longsword. 3 8
• Sister Doma — a small, cream-haired girl with twin tails, a dress, and a black rabbit plushie. 16
• Kurotama — a black-haired swordswoman in a black sailor-style dress, armed with Yatsufusa. 64 67
• Schubie — a female Mechanized Race body whose hair is durable enough to cut steel. 213

Personality

Su Lin is determined and unusually tolerant of hardship when training his avatars, especially Yukino. He repeatedly pushes their regenerative bodies through painful exercises to build strength, even when warned that his methods are dangerous. 2 3

Despite his strength, he is often lazy in routine matters. He sleeps through classes after working late, is confused by his election as Class Representative, and considers Tenya Iida better suited to the position. 9 11

He is calm and adaptable in unfamiliar worlds, preferring preparation, deception, and coordinated avatar use over unnecessary risk to his main body. He also shows consistent concern for vulnerable people, including Torhu, the Cursed Children, and the Misaka Sisters. 20 73 153

Su Lin considers every avatar to be part of his real identity rather than a separate person. Although he controls them with one consciousness, the System states that their original emotional patterns can influence him through their bodies. 9 213

Abilities & Skills

Clones / Avatar Manifestation

Su Lin can summon avatars as separate bodies or transform his main body into an avatar. Each form has distinct physical traits, skills, equipment, and duration limits. 4 81

• All avatars are controlled by Su Lin; he states that they do not possess independent personalities. 9
• He can use multiple bodies to multitask, train, fight, or perform different roles simultaneously. 1 101
• Destroying an avatar does not directly injure his main body. 2 26
• Avatar time limits vary by form; Kurotama, for example, can only remain manifested for a set period each day. 81
• Su Lin can use avatars as decoys and coordinate them in combat to mislead opponents. 9 146

Yukino Yukinoshita

Yukino is Su Lin’s earliest and most frequently used avatar. Her body possesses rapid regeneration and improves physically through injury and destructive training. 2

• Rapidly heals injuries sustained during training or combat. 2 38
• Gains physical strength from repeated high-intensity training. 2 199
• Provides advanced academic aptitude; Su Lin becomes fluent in English and excels in cultural classes while using her form. 7
• Later serves as the Demon Slayer Corps’ Mist Pillar despite not using Mist Breathing. 101

Mysterious Heroine X

Mysterious Heroine X is Su Lin’s primary decisive-battle avatar and one of his strongest direct-combat forms. 3 53

• Wields a sword and can create a second black blade for dual-sword combat. 3 30
• Uses techniques including Support Fire EX, Saber Star C++, Galaxy Meteor Sword C, Cosmic Reactor A, and Riding EX. 3
• Possesses the Noble Phantasm Nameless Victory Sword A++. 3
• Defeated Shoto Todoroki to win the U.A. Sports Festival. 30
• Her early five-minute limit makes prolonged combat and evasive opponents a serious problem. 3 53

Kurotama and Yatsufusa

Kurotama is a combat-focused swordswoman with assassination expertise and the cursed Imperial Armament Yatsufusa. 67 77

• Is nearly impossible to kill unless decapitated or stabbed through the heart, but suffers extreme agony without System-provided medication. 67
• Yatsufusa can control up to eight people it has slain as puppets, retaining their abilities and strength; controlling more puppets weakens Kurotama herself. 67
• Learns and practices Insect Breathing after Su Lin’s deal with Shinobu Kocho. 77
• Defeats Upper Rank Six, Gyutaro and Daki, then uses Yatsufusa to control their bodies. 98
• Is evaluated as a Level 5 esper in Academy City. 112 113

Main Body Training and Forging

Although Su Lin initially relies on avatars for combat, the System eventually allows his main body to improve through training, combat practice, and forging. 75 77

• Acquires basic instinctive combat movements through the Basic Proficiency Technique book. 82
• Learns the fundamentals of Total Concentration Breathing, though he cannot initially maintain it continuously. 89 90
• Opens a weapon shop in Demon Slayer Corps territory and forges demon-slaying weapons with scalable attributes. 76 90
• Produces Nichirin-style weapons, including blades with sharpness, frost, fire damage, and Demon Slayer attributes. 76 82 90

System and World-Level Powers

Su Lin’s System unlocks avatars, assigns quests, enables interworld travel, and adapts or restricts abilities according to each world’s rules. 75 87 185

• Can deploy forces from worlds the System has controlled when outside entities intrude. 86
• Can exploit worldview segmentation to exile enemies from a world; against that world’s inhabitants, the System describes exile as effectively equivalent to death. 157
• Grants access to God Strike, a large-scale attack based on extraordinarily pure laws. 213 262

Equipment / Weapons / Items

• Mysterious Heroine X’s sword — weapon used for her sword techniques and Noble Phantasm. 3
• Yatsufusa / Eight Servants of the Emperor — Kurotama’s cursed blade and puppet-controlling Imperial Armament. 67
• Rabbit Plushie — Sister Doma’s plushie redirects damage from Su Lin’s main body to Doma regardless of distance. 16
• Decapitation Blade — forged demon-slaying weapon with Sharpness +6, Weight +12, Firmness +3, Cutting +1, and Demon Slayer +1. 76
• Flame Demon Slayer Stone +1 — reinforcement material that gives Yatsufusa Fire Damage and improves its demon-slaying property. 82
• Basic Proficiency Technique — book that turns remembered techniques into basic instinctive movements. 82

Relationships

• Torhu Hagakure — Su Lin’s closest school friend and one of the few people aware that his main body is male. She supports him materially and emotionally, votes for him as Class Representative, and later develops feelings for him. 2 9 54 60
• Izuku Midoriya — classmate and occasional teammate. Midoriya admires Yukino’s training, works with Su Lin during combat exercises, and is rejected by Yukino when he develops feelings for her. 3 8 34
• All Might — observes Su Lin’s dangerous training, awards his Sports Festival medal, and becomes concerned that Su Lin may vanish from the future. 3 30 61
• Shota Aizawa — U.A. teacher who monitors Su Lin’s unusual Quirk and protects his privacy from excessive attention. 39 61
• Shinobu Kocho — enters a transaction with Su Lin: she gives him Insect Breathing in exchange for information and future help avenging her sister. She later discovers that his “girls” are avatars. 77 90
• Misaka Mikoto — ally in Academy City. She works with Su Lin to destroy research facilities connected to the Misaka Sisters project. 147
• Accelerator — initially an opponent; Su Lin defeats him and later offers assistance with his brain injury through an avatar. 147 158
• Saitama and Genos — fellow Hero Association recruits and neighbors in Z-City. 240
• His avatars — manifestations of Su Lin’s single consciousness; he ultimately accepts each body as a genuine part of himself. 9 213

Story Role / Major Arcs

U.A. High School

• Reveals his male main body while applying to U.A. and demonstrates that Clones is a combat-capable Quirk. 4
• Uses avatar tactics to win a team combat exercise against Tenya Iida’s group and is elected Class Representative. 9
• Receives a mandatory quest to completely eliminate the wielder of All For One. 10
• Represents Class 1-A at the Sports Festival and wins the first-year championship as X. 20 30
• Captures Toga to clear himself during the Forest Camp incident. 54
• Learns that his Quirk’s side effect will erase him from the world, then arranges farewell events for Class 1-A. 62

Black Bullet World

• Helps Cursed Children in the Outer District by teaching swordsmanship, funding improved living conditions, and prioritizing their direct protection over political reform. 72 73 74
• Refuses the Holy Child’s Seven Stars’ Legacy mission and later makes the Holy Child his informant before leaving the world. 73 74

Demon Slayer World

• Establishes a weapon shop, forges demon-slaying equipment, and enters a deal with Shinobu Kocho. 77 90
• Protects Nezuko during the Pillar Meeting through Kurotama and becomes involved with the Demon Slayer Corps. 82 83
• Prevents major conflicts, eliminates multiple Upper Rank demons, and has Yukino named the Mist Pillar. 98 101 103
• Eventually departs, leaving divine statues of his avatars at the Butterfly Mansion; the Corps regards him as a deity. 110

Academy City

• Enrolls Kurotama at Tokiwadai, where she is assessed as a Level 5. 112 113
• Investigates the Misaka Sisters project, defeats Accelerator, and destroys research facilities alongside Misaka Mikoto. 143 147
• Saves the Misaka Sisters through deception directed at Level Upper and Aleister. 153
• Is considered a possible Level 6 and prepares to banish the Demon Gods phase through rule analysis. 163

Later World Travel

• Enters the Sword Art Online world after obtaining Kanade Tachibana. 185
• Reaches Black Ash six thousand years before No Game No Life and assists Rikku’s human group against a Demon Race threat. 199
• Acquires Schubie and a dog-eared avatar before being sent toward the Akame ga Kill! world. 213
• Joins the Hero Association in the One-Punch Man world, begins as A-Class, and later participates in the 22nd Super Fighting Tournament as an S-Class hero. 239 240 259

Notable Quotes

“Infinite Possibility, Fleeting Shadow!” — Su Lin’s chosen hero name 33

“They are all controlled by me. I wish they had their own personalities, but in reality, it's all just me.” 9

Trivia

• Su Lin’s U.A. application listed his gender as female because he was in an avatar state when the record was made. 4
• Nighteye cannot clearly perceive Yukino’s future, seeing only distorted images. 57
• Su Lin’s hero name reflects both the unknown future of his avatar roster and his belief that he is only a “fleeting phantom” in the worlds he enters. 33