Katana Man

Katana Man, real name unknown, also known as Samurai Sword (サムライソード, Samurai sōdo) is a human-devil hybrid who merged with the Katana Devil. His grandfather was the Mob Boss killed by Denji and because of that he affiliated with the Gun Devil to get revenge on Denji.

He is the primary antagonist of the titular Katana Man arc.

Appearance
The Katana Man is a tall man with a short black hair and notable sideburns. He normally dresses in a large leather coat.

When he transforms into his hybrid form he grows large swords from each of his arms and his face takes on a demonic appearance with dark skinless flesh and oversized jaw devoid of lips. His chin becomes pointed and another sword grows from his forehead where his eyes would be, with the handle sticking out of the back of his head.

Personality
The Katana man is selfish and cruel. He only cares about killing Denji and forcing him to apologize for killing the Katana Man's grandfather. He will sacrifice innocent people and even his own comrades to do so, being willing to cut through them just to get to Denji. He has shown a complete disbelief in Denji's excuse that he killed his grandfather because he was a zombie, and accused Denji of being a liar.

He loves his grandfather despite knowing he was a Yakuza boss because he viewed his grandfather as a man of principles who had only killed a handful of women and children.

Despite having his physical heart replaced with the Katana Devil, the Katana Man considers himself to still have a human conscience and states that he doesn't sleep well on nights where he killed a zombie, in contrast to Denji who has no guilt at all.

History
At some point he had an arrangement with Akane Sawatari where his heart was replaced with the Katana Devil by her, allowing him to transform into a hybrid.

Katana Man arc
The Katana Man ate at the same restaurant as Denji, Aki, Himeno and Power. He commented that the food was disgusting and went into a speech about refined taste and how a person's upbringing will affect them. As the others considered leaving instead of responding to him, he brought up his grandfather and showed Denji a picture of the Yakuza boss that Denji worked for in the past. Before Denji could react the Katana Man pulled out a pistol and gunned down Denji, Himeno and Aki. Power swiftly moved out of his sight and hit him with an uppercut to knock him back. Aki summoned the Fox Devil in that opening which swallowed the Katana Man, however the Katana Man swiftly cut himself free after transforming.

Aki draws out a spike with a sword hilt and engages the Katana Man. The Katana Man is stabbed three times in a row by Aki which summons the Curse Devil. The Curse Devil grabs the Katana Man and violently kills him. Akane Sawatari appears in the ruined building and crouches down near the Katana Man, reviving him. As Aki watches in shock the Katana Man dashes forwards and slashes Aki.

Before the Katana Man can finish off Aki, Himeno intervenes by using the full power of her Ghost Devil to overwhelm him. Unable to effectively fight back, the Katana Man begs Akane for assistance and she uses her Snake Devil to swallow the Ghost Devil while Himeno's body vanishes. In her final moments Himeno pulls Denji's chainsaw cord to revive him. The Katana Man and Denji charge at each other as the Katana Man swears he'll put Denji down a second time.

The Katana Man and Denji clash multiple times, destroying the building around them. The Katana Man's subordinates arrive to back him up and he tells them to aim for Denji's arms or his heart. Denji takes one of them hostage but the Katana Man uses his dashing technique again to blitz Denji at high speed and cut through both Denji and the hostage. With Denji bisected and defeated, the Katana Man's transformation became undone and he reverts to his human form while declaring victory over the Devil Hunters who can't stand up to the power of guns.

The Katana Man and Akane lead their people outside to a van that they're trying to load Denji into, but suddenly his subordinates start dying around him.

Akane tells him that they should escape while they still can, and that it is likely that Makima herself is attacking. Cursing, the Katana Man tries to pick up Denji but notices Kobeni approaching them. Akane tries attacking her with the Snake Devil but Kobeni nimbly avoids the attack and runs across its body towards them. He tries gunning her down but Kobeni cuts off his arm and catches his gun, shooting him twice in the back. When Kobeni runs out of bullets Akane escapes after throwing the Katana Man's body inside the van.

Kishibe tells Denji and Power that their first mission of real combat will be to capture the Katana Man and his accomplice Akane. At his hideout the Katana Man is fuming over Denji and tells his underlings that he won't run away, just like how his grandfather wouldn't. Akane tells their subordinates not to worry about their boss since even if he dies he will be revived.

Akane tells the Katana Man that they'll kill as many devil hunters as possible and try to steal Denji's heart if possible before escaping through the Snake Devil. The Katana Man swears he'll kill Denji, while Akane tells him not to lose his cool.

During the raid on the Katana Man's hideout, Denji took the elevator by himself after Power disembarked to fight some zombies and he encountered the Katana Man with a couple of his subordinates. Instead of fighting right away the Katana Man offered depending on Denji's attitude. He demanded that Denji allow himself to be killed without resistance in order to satisfy the Yakuza's anger, but Denji refused leading to both of them transforming at the same time. The Katana Man charged at Denji, sending both of them flying through the wall and they clash in the air outside.

Denji lands on a train, followed by the Katana Man who knocks him through the roof of the carriage and into the train. The Katana Man blitzes Denji twice in quick succession while Denji tries to protect a civilian, leading to both of Denji's arms being cut off. The Katana Man demands once more than he apologize for killing his grandfather but Denji claims he can still fight because he has the chainsaw on his head. The Katana Man, baited by Denji's words, charges at him a third time and shatters the chainsaw on Denji's head while simultaneously being cut in half by a new chainsaw that Denji sprouted from his legs. Denji calls him a moron while the Katana Man falls apart.

After recovering, Denji pulls the arm katana out of the Katana Man causing his body parts to stick back together and for him to revert back to his human form. He is then tied up with a chainsaw chain and stripped to his boxers while Denji waits for Aki to arrive. Denji thinks of some way to get payback against the Katana Man for shooting Himeno, and as Aki arrives he announces that he will hold a tournment; whichever ones of them gets the biggest scream of pain from kicking him in the nuts wins. Aki is initially reluctant but changes his mind after looking at Himeno's cigarrete which has "Easy revenge!" written on it. The two then take turns kicking him as as their way of paying respect to Himeno.

Bomb Girl arc
Denji recalled the Katana Man's method of dashing forwards at high speed and starting thinking about how he could apply his own powers towards mobility as a result.

Abilities
Katana Devil Transformation: By removing his left hand from his body and revealing a katana which emerges from the stump, he can transform into the Katana Man form with swords emerging from his arms and his head. Removing the katana from his arm will undo his transformation. After his transformation is undone he is unable to fight for a while.
 * Enhanced Strength: The Katana Man's strength is greatly enhanced in his transformed state, able to cut through solid walls with his slashes.
 * Sword-Draw Dash: By crouching down low and preparing to unleash his swords, the Katana Man could dash forward at incredible speeds and slash at his opponent as he goes by them, often appearing to simply teleport past them before his attacks appear on his opponents body.

Blood Consumption: As a hybrid, the Katana Man should be able to restore his health by consuming blood.

Skillset
Marksmanship: In his human form the Katana Man has used a handgun to gun down Denji, Aki and Himeno at close range.

Swordsmanship: The Katana Man is a skilled fighter with his arm blades, able to clash against Aki and Denji and ultimately overwhelm them with his powerful slashes.