Gilbert Butler serves as the Chancellor, or Prime Minister, of the Freesia Kingdom. His background is one of humble and troubled beginnings. Coming from a low social status, he spent his youth as a delinquent engaged in nefarious activities. His life took a transformative turn when he met Marianne, a highborn young woman suffering from an illness that confined her to her home. Despite the differences in their social standing, her kindness and unique perspective on life moved him deeply. He abandoned his criminal ways to better himself, driven by the promise of one day being worthy of her. Years later, after discovering his special ability and working tirelessly to rise to the prestigious position of Chancellor, he proposed to Marianne, who accepted. However, their happiness was short-lived as she soon fell victim to an incurable disease.

In terms of personality, Gilbert initially presents a mysterious and somewhat antagonistic facade. His blue hair and sharp-tongued, sarcastic remarks often make his true intentions difficult to read, leading others to find his "vibe" suspicious or off-putting. This behavior is not born of malice but of sheer desperation. Beneath this cold exterior lies a profoundly devoted and loving individual whose every action is motivated by a single goal: saving his dying fiancée. His desperation drives him to extreme lengths. He is also an incredibly hardworking and brilliant strategist. Lacking the privilege of a distinguished lineage, he climbed the social ladder purely through intellect and effort. He possesses exceptional intelligence and masterful information manipulation skills, earning him a reputation as someone capable of instigating a revolution single-handedly.

Gilbert's primary motivation throughout the story is the desperate search for a special ability user who can cure Marianne's fatal illness. This singular focus defines his role in the narrative. In the early stages, this desperation puts him in direct conflict with Princess Pride. Believing her to be an obstacle, he spreads false rumors and commits crimes, including selling confidential information and colluding with political committees, hoping to remove her from power to further his search. He confesses to these acts, which include treason and illegal dealings, demonstrating how his love drove him to betray his kingdom.

His key relationships are central to his character arc. His relationship with Marianne is the emotional core of his story; she is the catalyst for his reformation and the object of his unwavering devotion. He is also a close friend of Prince Albert, who is five years his junior, despite their frequent disagreements where Albert punches him for his sarcastic comments. His relationship with Princess Pride evolves dramatically. Initially an enemy, he becomes her most loyal subject after she saves Marianne's life by orchestrating a cure using Arthur's abilities. Overcome with gratitude and regret, he swears absolute loyalty to her, saying he will serve her for the rest of his unnaturally long life, viewing her with a sense of idolization. His relationship with Prince Stale remains more complex; while they come to share a mutual respect, Stale admits to despising him, a feeling that Princess Tiara suggests stems more from jealousy over Gilbert's status and maturity than from genuine hatred.

Gilbert undergoes significant development. He starts as a desperate antagonist willing to commit treason for love. Through his backstory, he is humanized from a suspicious figure into a tragic romantic hero. After being shown mercy and receiving help from Pride, he is redeemed. He willingly confesses his crimes and submits to judgment. Instead of a harsh punishment, Pride orders him to take a solemn vow to dedicate his life to serving the land and its people forever, a punishment he accepts with utmost humility and gratitude. This act solidifies his change from a man willing to tear down the kingdom to one sworn to protect it for eternity.

Gilbert possesses the notable special ability of age manipulation, which effectively grants him eternal youth. He can alter his own apparent age at will, a power that proves useful for espionage and infiltration, as he can assume the form of a child or an elderly person unnoticed. This ability also means he can, in theory, serve the kingdom indefinitely as its Chancellor, living out his vow of eternal service. Combined with his genius-level intellect, mastery of martial arts honed in the lower class, and expertise in strategy and manipulation, Gilbert Butler is an exceptionally capable and formidable individual.