Yi Sungjin

Yi Sungjin is a Korean Earthling, the younger brother of Yi Seol-Ah, and a shield-bearing Warrior of Valhalla. He enters the Tutorial as a sixteen-year-old Bronze Mark and initially depends on his sister and Seol Jihu for survival. Repeated training and an expedition undertaken without Valhalla's senior members turn him into a reliable Guard who protects other combatants rather than waiting to be protected. He later reaches Level 5 Royal Guard and survives the final war.

Biography

Loss and dependence in the Tutorial

Sungjin arrives in the Tutorial holding close to his older sister. When the Gaekgwi kills Seol-Ah, he searches desperately for a way to revive her and responds immediately when Seol says such a method may exist. Seol eventually uses the revival medicine found by Yun Seora, restoring Seol-Ah and giving the siblings a second chance together. Their gratitude becomes the foundation of Sungjin's attachment to both benefactors, but at this stage he remains a frightened minor following decisions made by stronger people. (Chapters 4–9)

In the Neutral Zone, Sungjin shares the siblings' limited resources and accepts Seol's help with food, Survival Points, and training access. Seol directs him toward fitness work under Competence, while the household formed by Seol, the Yi siblings, and Yun Seora gives him a stable routine. This period begins his physical development but also establishes the dependence he must later overcome: his opportunities come through Seol's resources and the protection surrounding his revived sister. (Chapters 13–19)

White Rose and Carpe Diem

The siblings join White Rose after the Neutral Zone, trusting Bok Jungsik, but the organization later admits that it has not cared for them adequately. When White Rose dissolves, richer organizations are interested in acquiring the talented Seol-Ah, while Sungjin is generally treated as part of the pair. They choose Carpe Diem instead. Sungjin introduces himself simply and promises to work hard, accepting a smaller team whose protection and personal ties matter more than the highest financial offer. (Chapters 75–80)

Carpe Diem does not mistake membership for readiness. Sungjin remains behind during the Arden Valley war and is visibly nervous when the senior members depart. He visits the injured Seol afterward and pays enough attention to notice changes in Jang Maldong's mood. When he wants to join the dangerous Pagoda of Dreams expedition, Seol refuses because his level and experience are still too low. Sungjin responds to those exclusions by volunteering for further training rather than demanding a battlefield place he cannot yet hold. (Chapters 85, 94, 106, and 120–122)

Training and a place in Valhalla

Sungjin's Warrior path centers on the large shield he trains to hold against overwhelming force. In a dream trial, he stands at the foot of a slope and receives a rolling boulder against a body-sized iron shield, illustrating the defensive burden his class is being built to bear. He follows Carpe Diem to Eva and calmly proposes “Valhalla” as the new organization's name. His contributions during this phase are mostly training, household participation, and support rather than independent combat, but they give him a permanent institutional home. (Chapters 120–137)

When Valhalla formalizes teams, Sungjin is a Level 3 Guard assigned to Team 1 under Phi Sora, alongside Seol-Ah, Ghionea Marcel, and Maria Yeriel. The placement recognizes a defined defensive role while also exposing his lack of expedition experience. Kim Hannah warns the siblings that full members must solve problems without relying on Seol's name. Sungjin accepts the criticism, says the mistake will not recur, and immediately looks for a way to gain the experience expected of him. (Chapters 161 and 163)

An expedition without senior protection

Sungjin joins a small outside expedition even after its leader says the siblings will receive no share and may be abandoned if they become burdens. He offers to carry equipment because he wants experience and hopes Paradise can help heal his mother. During the expedition, he interposes his shield to push the leader away from a monster's attack, saving the man's life. The group that initially viewed him as a liability returns praising his performance and asks him to accompany future trips so its Barbarian Warrior can fight freely behind a Guard. (Chapter 163)

That success changes Sungjin before it changes his title. He returns with a shield bearing a reflection ability and joins Team 1's operation against a traitorous Bishop. When a Priest launches a cluster of light at Phi Sora, Sungjin places himself in front of her; the shield sends the attack back and strikes its caster. The action shows the practical result of his independent expedition: he has acquired both equipment and the timing to protect a stronger teammate during a live confrontation. (Chapters 169–170)

War and maturity

After Seol's body returns from the Imperial Oath expedition, Sungjin helps Kim Hannah restrain the distraught Jang Maldong and notices that Kim needs to move despite her exhaustion. The scene places him in a stabilizing role off the battlefield as well as on it. By the next status review, combat during the crisis has raised him to Level 4. Seol then spends a Divine Wish to complete another promotion, making Sungjin a Level 5 Royal Guard before the final campaign. (Chapters 188 and 194)

Sungjin advances with Valhalla in the final war, raising his shield as the team approaches the last enemy line. He is not presented as the force that defeats the Parasite Queen; his responsibility is to hold formation among much stronger veterans. He survives the war and remains one of Valhalla's Warriors. Later Team 1 records place him beside Chung Chohong, while Seol-Ah and Marcel provide ranged support, showing that his shield role has become part of a balanced expedition team rather than an apprentice assignment. (Chapters 197 and 248)

Life after the war

On Earth, Sungjin remains the younger and more restrained of the Yi siblings. He is still a minor at a reunion, declines alcohol, apologizes for his sister's drunken behavior, and gets her home. Later he is described as having grown into a handsome young man while retaining his respectful address for Seol. These scenes show ordinary maturation continuing alongside his Paradise class growth instead of treating Level 5 as an instant transition into adulthood. (Chapters 221 and 224)

By the latest chapter, Sungjin is alive, active in Valhalla, and close to both Seol and Seol-Ah. When Seol introduces his parents to the organization, Sungjin protests his sister's deliberately provocative self-introduction because he understands the formality of the moment. His latest role is therefore consistent with his development throughout the story: he is rarely the loudest person present, but he notices what others need and tries to keep both battles and social situations from going out of control. (Chapter 253)

Appearance and personality

Sungjin is introduced as a sixteen-year-old Korean boy who stays close to his eighteen-year-old sister. Later scenes show him wearing glasses, armor, and carrying a body-sized shield. By the postwar side stories he has physically matured into a handsome young man, though he remains younger than Seol-Ah and is still treated as a minor at an Earth-side reunion. The corpus does not provide his height, weight, or a complete Status Window. (Chapters 4, 122, 170, and 221–224)

He is polite, observant, and more reserved than his sister. Early fear and grief make him dependent, but they do not prevent him from helping others or accepting demanding instruction. He responds to criticism with a direct promise to improve, takes an unfavorable expedition deal without invoking Valhalla's influence, and earns respect by protecting a teammate. In domestic scenes he consoles Seol-Ah, apologizes for her excesses, and recognizes when ceremony matters. His maturity develops through responsibility rather than through a sudden change in temperament. (Chapters 8–19, 94, 159–170, and 221–253)

Abilities and class

Sungjin progresses from a Bronze Mark entrant to a Level 3 Guard, Level 4 Warrior-path Earthling, and Level 5 Royal Guard. His class development is defensive: he trains with heavy shields, places himself between attackers and teammates, and creates space for less durable allies to perform their roles. The corpus does not provide a named final skill list, so Royal Guard should not be treated as proof of abilities that are never demonstrated. (Chapters 4, 122, 161, 194, and 197)

His clearest demonstrated technique is the reflection ability attached to a shield acquired during his independent expedition. It returns a Priest's light attack to its source when Sungjin intercepts the spell in front of Phi Sora. He also uses ordinary guarding fundamentals—reading an incoming strike, cutting between a monster and its target, and physically pushing the endangered person clear. These feats depend on positioning and equipment as much as raw durability. (Chapters 163 and 170)

Sungjin's limitations remain visible. Senior members exclude him from high-risk expeditions while he is low-level, and even after reaching Royal Guard he advances as part of a formation rather than fighting elite enemies alone. His value is protective reliability: he lets a Barbarian Warrior attack without guarding the rear, shields a team leader from magic, and later fills one of Team 1's two Warrior positions. Nothing in scope establishes a Unique Ranker realm or a broad offensive arsenal. (Chapters 85, 106, 163, 170, 197, and 248)

Power progression

Relationships

• Yi Seol-Ah: Seol-Ah is Sungjin's older sister and first protector. Her death drives his early search for revival, while her return keeps the siblings together through the Neutral Zone, White Rose, and Valhalla. As they mature, the balance becomes less one-sided: Sungjin accepts criticism faster, saves an expedition leader, consoles Seol-Ah, and sometimes manages the consequences of her impulsive behavior. (Chapters 4–19, 75–80, 159–170, and 221–253)
• Seol Jihu: Seol revives Seol-Ah, supplies the siblings in the Neutral Zone, arranges training, and later sponsors Sungjin's promotion to Royal Guard. Sungjin calls him Hyung and repays protection through loyalty rather than a formal debt. His growth is clearest when he stops relying on Seol to secure an expedition place and returns with experience of his own. (Chapters 8–19, 75–80, 106–170, and 194–253)
• Phi Sora: Phi becomes Sungjin's Team 1 leader and a demanding source of field discipline. Sungjin reports to her after his outside expedition and later protects her by reflecting a Priest's attack. Their relationship shows the difference between being sheltered and being trained: Phi expects initiative, but provides the command structure in which his defensive specialization can mature. (Chapters 161–170)
• Jang Maldong: Jang oversees the harsh training that develops Sungjin's shield work and physical endurance. Sungjin notices the old man's moods and, after Seol's apparent death, helps calm him when grief threatens to overwhelm judgment. The student eventually supports the teacher emotionally as well as receiving instruction from him. (Chapters 94, 120–122, and 188)
• Maria Yeriel and Ghionea Marcel: Maria and Marcel are senior specialists in Sungjin's original Team 1. Their healing and ranged power benefit from a Guard who can hold enemies away, while their experience emphasizes how junior he initially is. Later team records retain Sungjin in a balanced formation with both specialists, confirming that his role endures after promotion. (Chapters 161, 170, and 248)

Items

• Reflection shield: Sungjin receives a shield with a reflection ability from the party he joins on his first independent expedition. He uses it to intercept and return a light attack aimed at Phi Sora. The shield is important to his demonstrated combat growth, but the corpus does not provide a unique name or a complete list of its properties. (Chapters 163 and 170)