Wangnan is depicted as a young man with blond hair and yellow eyes, distinguished by a small mole beneath his right eye. A notable physical trait is the pair of red protrusions that extend from behind his ears, along with the presence of two sharp fangs. He is also seen wearing a ring engraved with Zahard’s emblem, identical to the one worn by Karaka.

His typical attire consists of a jumpsuit-style outfit layered with a detailed coat, often paired with a formal suit underneath. Throughout the series, Wangnan is shown in various outfits, including jackets, suits, and casual summer clothing, reflecting the different contexts of his journey.

Wangnan is portrayed as ambitious and confident, with the bold aspiration of one day conquering the Tower and ruling over it. Central to his character is an unyielding determination; no matter how many setbacks he experiences, he continues to push forward. His practicality is also evident, particularly during tests, where he often prioritizes strategy over sentiment, such as suggesting the elimination of the strongest-looking participant during a voting round.

Despite his pragmatic outlook, Wangnan demonstrates empathy toward others, even those who have betrayed or opposed him. He forgives Nya Nia after understanding the reasons for his betrayal and shows compassion toward Kim Lurker, recognizing their shared circumstances. This balance between practicality and conscience defines his inner struggle, as he frequently wrestles with reconciling his morals with the harsh realities of the Tower.

His persistence is highlighted during his time on the 20th Floor, where, unlike his companions who eventually abandoned the climb, he continued to endure the challenges alone. Burdened by debt and isolation, he nevertheless refused to surrender, holding onto hope even in despair, an experience that parallels Baam’s earlier isolation in the cave.

In addition to his resilience, Wangnan possesses natural leadership qualities. Noted by Khun, he is capable of rallying diverse individuals, even those with volatile personalities such as Quaetro Blitz, earning their trust and loyalty through his resolve.

Series creator SIU described Wangnan as a “Test Jaesusaeng” (시험 장수생, Siheom Jaesusaeng), a phrase meaning “long-time test taker.” This alludes to his unusual age and longevity, with implications that he is old enough to be considered a “brother” to Karaka.

Wangnan was born in the Red Light District, though he has no personal memory of the place. He was raised by a nanny who told him that the district had already been destroyed before they departed. On his tenth birthday, she gave him a ring as proof of his status as a prince. When the nanny later fell gravely ill, she confessed on her deathbed that she regretted failing to raise “the king’s seed” properly, a revelation that left Wangnan devastated, as he realized she had never truly regarded him as her own child. After her passing, a mysterious man appeared, claiming to be an acquaintance of the nanny. He took her body away and advised Wangnan to safeguard the ring, explaining that it was a vital key within the Tower. He further instructed Wangnan to seek confirmation if he ever encountered another bearer of the same ring.

Wangnan eventually became a Regular and entered the Inner Tower. Upon reaching the 20th Floor with a group of companions, he and his team were unable to clear the tests. Over time, all of his friends abandoned the climb, leaving him to struggle alone. Despite being isolated in debt and despair, Wangnan persisted, surviving on little more than hope.

In later visions, it is revealed that many of Wangnan’s companions perished during their attempts to climb the Tower with him. His perseverance eventually brought him into contact with Team Tangsooyook, marking a new stage in his journey.

Ja Wangnan is considered relatively weak compared to other Regulars, often struggling in physical strength and Shinsu control. Despite this, he demonstrates notable persistence, tactical thinking, and leadership skills that allow him to overcome challenges and earn the loyalty of allies.

General Capability
Wangnan’s abilities are generally below average for a Regular. He repeatedly failed the tests on the 20th Floor, to the point of bankruptcy and heavy debt, and was frequently forced to evade loan sharks. He ranked fifteenth in the “World’s Strongest Regular Test,” which emphasized Shinsu strengthening, highlighting his limited proficiency in this area. Physically, his strength ranges from weak to average, though he has shown bursts of power, such as striking an opponent with enough force to launch them several meters.

Agility
While lacking raw power, Wangnan has displayed agility and evasive skills. He was able to avoid attacks from Jyu Viole Grace, albeit while Viole was restraining his abilities, and has been seen maneuvering along walls during combat.

Weapons and Tools

• Shinsu Bombs: His primary offensive technique involves an array of Shinsu-based bombs, tailored for different situations. These include explosive bombs, pepper bombs designed to blind or incapacitate, and smokescreen bombs used for cover or retreat. He has demonstrated accuracy with these weapons, successfully striking opponents such as Mule Love from long distances.
• Arms Inventory: Wangnan possesses an Arms Inventory that primarily consists of Shinsu Bombs, alongside a black needle and a Reel Inventory.
• Speaking Sword: During the Hidden Floor arc, Wangnan acquires a speaking sword capable of teleporting itself and nearby individuals within its range.

Endurance and Regeneration
Wangnan has shown unusual resilience to life-threatening injuries. After being stabbed in the heart by Beta, he managed to remain conscious and summon Viole before recovering fully within a day. Later, during the Hell Train, his nearly severed hand healed within weeks with only basic treatment. The source of his regenerative ability remains unexplained.

Leadership Qualities
Khun Aguero Agnis recognized Wangnan’s natural leadership potential, appointing him as the team’s Vanguard not only due to his combat limitations but also for his ability to unify diverse individuals. Wangnan has persuaded volatile allies such as Quaetro Blitz to join him, helped Viole reopen himself to friendship, and even influenced Ha Jinsung, a high-ranking FUG member, to spare his group.

Potential
Although Wangnan is not initially portrayed as a powerful combatant, series creator SIU has hinted at latent potential, suggesting that his true strength may emerge later in the story.

The name Wangnan (왕난) can be broken down in Korean as wang (왕), meaning “king,” and nan (난), which can mean “difficult” or “trouble.” Together, the name has been interpreted as “difficult king” or “troubled king,” a possible reflection of his struggles and ambitions to become ruler of the Tower.

His surname Ja (자) does not have a clearly stated meaning in the series, though it may carry connotations of “self” or “seed” depending on the context in Korean, which aligns with his background as one of Zahard’s princes.

The symbolism of his name, paired with the ring bearing Zahard’s emblem, emphasizes both his identity as a hidden heir and the hardships that define his path.