Adel Vandale, the Seventh Prince, is cruelly stripped of his title and banished by his father, King Charles Vandale, in the royal palace. Charles, an arrogant monarch obsessed with the Vandale family's tradition of producing "Sword Saints," deems Adel's newly acquired "Executioner" job useless and a disgrace after it fails to manifest any abilities during a mock battle. As Adel bows in resignation, a mysterious blue text appears before him, displaying "Target: Charles Vandale, Execution Coefficient: 12,850,904 points," a phenomenon he doesn't yet comprehend.
Cast out and penniless, Adel endures extreme poverty, scavenging for food and water. His attempts to become an adventurer are sabotaged by false rumors spread by Charles, accusing Adel of theft and attacking his father. This period of intense suffering fuels Adel's desire for power to "destroy such injustice." His wish is answered when he is attacked by notorious bandits. Facing death, the blue text reappears, and Adel instinctively summons a jet-black scythe, "Igarima," which effortlessly shatters an orichalcum sword. The terrified bandits flee, and Adel discovers his "Executioner" job allows him to "execute" targets, gaining "Execution Coefficient" points.
Two years later, Adel operates as the "Black-Clad Executioner," running a tavern called "The Silver Apple Inn" with his loyal maid, Meia. Meia, whom Adel saved in the past, is fiercely devoted to him and assists in his "Revenge Agency," which eradicates injustices caused by "scumbags." Adel believes revenge can be a powerful "wish" for those suffering.
Their next client is Lilina Bartley, the eldest daughter of a noble family. Lilina was banished by her father, Gale Bartley, a "Holy Knight" obsessed with his "Gale-style" sword techniques, because she received the "Tamer" job instead of a sword-related one. Gale is now subjecting her younger siblings to brutal, life-threatening training, viewing them as mere tools to strengthen his family's ties with the royal family. Adel, recognizing the Bartley family's connection to the Vandale Royal Family, accepts the emotionally charged request. He demonstrates his power by revealing Gale's high "Execution Coefficient" (7,023 points) and summoning Igarima, which grows stronger with higher coefficients, astounding Lilina.
Adel, Meia, and Lilina confront Gale in the Bartley courtyard. Adel intervenes when Gale attempts to physically abuse his youngest child. Gale, arrogant and unrepentant, attacks Adel with his "Holy Knight" abilities, but Adel effortlessly evades him. Declaring that Gale's "job is everything" mentality is flawed, Adel uses Igarima to "reap" the source of Gale's job ability, rendering him powerless. Gale collapses in despair, his identity shattered. Adel then forces Gale to sign a magical "Oath Scroll," transferring all family authority to Lilina. To ensure compliance, Adel summons a powerful "Hellhound" (an ability he gained from a previous execution), which Lilina effortlessly tames, further humiliating Gale and proving her own worth. Adel learns that the Vandale Royal Family had been secretly encouraging Gale's actions, confirming Adel's suspicions about his former family's machinations.
Meanwhile, King Charles receives a report of Gale's defeat and the transfer of power. He is enraged that his "plan" to cultivate talent for the royal family has been disrupted by the mysterious "Black-Clad Executioner." Dismissing Gale's loss of job ability as weakness, Charles briefly recalls Adel, believing his "useless" son to be dead, unaware of the irony. He is also revealed to be involved with the "Roenthal Trading Company" as part of his larger, secret plan.
The "Black-Clad Executioner's" fame spreads. Marie, a flower shop owner in the Royal Capital Lydale, reads about his heroic deeds. Her own shop is under threat from the aggressive "Roenthal Trading Company," which, backed by the Royal Family, is demanding eviction to build a brothel. Marie, whose shop was once saved by the Seventh Prince (Adel) years ago, feels desperate and wishes for help. Adel and Meia, on a supply run, witness the Roenthal thugs harassing Marie. Adel and Meia swiftly intervene, driving off the thugs. Marie, recognizing Adel as her rescuer, tearfully pleads for his help to save her beloved shop. The narrative progresses from Adel's personal banishment and awakening to his established role as a powerful, justice-seeking figure, now directly confronting the injustices connected to his past and the corrupt royal family.