Kelb is introduced as a figure of significant authority, serving as the commander of the Royal Army under King Gilgamesh. During the Summer of Anu campaigns, he leads the kingdom's military forces into the Tower of Druaga with the declared mission of eradicating monsters and finally defeating the demon Druaga. In this capacity, he wields a massive two-handed sword, favoring a direct and powerful approach to combat.

His personality at the outset is defined by a strong sense of military pride and discipline. He holds the independent adventurers known as climbers in considerable contempt, viewing them as disorganized and undisciplined individuals who lack the camaraderie and structure of his royal soldiers. This dismissive attitude extends specifically to the young guardian Jil, whose non-military approach to the tower Kelb initially scorns, believing firmly in the superiority of the army he commands. Despite his stern and authoritative demeanor, he has a history as a mentor, having previously trained Ahmey during her service in the army.

Kelb's motivations evolve significantly over the course of the story. Initially driven by duty and a belief in the might of the Uruk Kingdom, his perspective shifts as he witnesses firsthand the limitations of the Royal Army when faced with the true perils of the tower and the full threat of Druaga. This experience leads him to recognize the potential and value of the very climbers he once dismissed. Following Druaga's second defeat, a major turning point occurs when King Gilgamesh falsely claims sole credit for the victory. This act of deceit and perceived dishonor leads Kelb to resign his commission from the army, disillusioned by his king's actions. He then transitions to a civilian life, opening a tavern near the tower. In this new role, his motivation shifts from conquest to providing shelter and support, allowing the betrayed and weary Jil and Fatina to recover at his establishment.

His role in the story is thus twofold. In the first season, The Aegis of Uruk, he is a leader of the military force competing with the climbers. By the second season, The Sword of Uruk, he has become a crucial ally and protector for the main characters. When the mysterious girl Ki appears and political tensions in Uruk escalate, Kelb leaves his tavern to investigate the truth behind King Gilgamesh's immortality and the connections between Ki, Kaaya, and the tower itself. His investigation uncovers the king's curse and the emergence of a Shadow Gilgamesh. Aligning himself with the rebellion led by his former comrade Ethana, Kelb plays a decisive role by delivering vital reinforcements to the city of Uruk during the climactic conflict. He directly confronts and defeats the true physical body of King Gilgamesh while Jil and Kaaya battle the king's shadow manifestation.

Key relationships define his journey. His bond with Ethana, his loyal lieutenant, deepens from professional respect to a life partnership, and they marry after the rebellion's success. His mentorship of Ahmey establishes a connection to the younger generation of climbers. Most significantly, his relationship with Jil transforms from initial disdain to one of mutual respect and support, as Kelb ultimately provides the young hero with a safe haven and, later, critical aid in the final battle.

In terms of development, Kelb undergoes a profound change from a rigid, prideful military commander to a humble tavern keeper who fights against a tyrannical king for the sake of truth. A notable moment of this personal growth occurs when he publicly apologizes to the climbers for having looked down on them, acknowledging his过去的错误. His journey concludes not on a battlefield but in peace, having abandoned his military and rebellious path to start a new, quiet life with Ethana. His notable abilities include high military authority and considerable personal combat prowess, specifically wielding a large two-handed sword with great effectiveness in battle.