Yukitou Youji appears to be an ordinary young part-time deliveryman and bicycle enthusiast traveling across Japan, but he leads a double life as an executioner for the criminally insane. His weapon of choice is a single metal spoke pulled from his bicycle wheel, which he uses to deliver cold vengeance to villains who have evaded the law. The setting is 1980s Japan, a world filled with corrupt police officers, greedy loan sharks, evil doctors, and powerful criminals who abuse the innocent without consequence.

The narrative begins with episodic, self-contained chapters in which Youji arrives in different towns, witnesses some act of cruelty or injustice, and eliminates the perpetrator. The opening chapter introduces a young man named Seiji, an ex-convict trying to live honestly, who is relentlessly harassed by a crooked detective. When the detective rapes Seijis sister and then kills Seiji in a staged self-defense shooting, Youji abandons his mild-mannered delivery boy persona, dons a black outfit, and executes the detective in a bar bathroom. These early chapters establish the series signature tone of ultraviolent retribution against irredeemable villains.

As the story progresses, Youji gains allies. Matsuda Kyouji is a former detective with an aggressive, hard-drinking personality and near-superhuman durability, described almost as an immortal monster. He becomes Youjis primary partner after the two cross paths during a case. Reira, also known as Leila, is a beautiful knife-wielding assassin who was raised by the criminal organization Dragon Fang Society but later betrays them to join the Black Angels. She operates with her own code, accepting money from wronged clients while using the phrase death fee as she carries out her killings.

The central antagonistic force is the Dragon Fang Society, also called the Dragonsfang Syndicate, a giant evil organization with grand ambitions and a seemingly endless supply of martial artist fighters and bizarre assassins. The series shifts into a more structured battle narrative when Youjis backstory is revealed, explaining how the Black Angels came to oppose this syndicates doomsday plan.

From this point, the manga transforms into an intense and often bizarre battle shonen. Youji and his companions face increasingly outlandish enemies employing strange martial arts techniques worthy of other hyper-masculine 1980s action series. Following a surprising plot twist, the story enters a post-apocalyptic arc in which various warlords fight over a mysterious and important object. The final major storyline is the White Angels arc, which upends the series premise by introducing weird superpowers and a new group of villains that the main characters must confront.

Throughout its run, the manga maintains a reputation for deeply shocking and traumatic scenes. Innocent characters, including children and elderly people seeking revenge, are brutally killed by villains before they can see justice served. A subplot involving an orphanage and a young girls savings being destroyed by corrupt developers exemplifies the series willingness to show the worst of humanity before the Black Angels deliver their grim brand of punishment.