- Awesome Art: The art in this series is on par with the likes of Berserk and Jojos Bizarre Adventure in terms of detail and quality, especially in its depiction of martial arts and the human body in motion. This actually serves to make the gory violence even more disgusting and horrific, but at least there's a lot of Scenery Porn and Costume Porn to compensate.
- Big-Lipped Alligator Moment: The arc which starred Gannosuke (aka Toad Guy). Apart from the fact that Gannosuke takes part in the tournament, he had little to do with Fujiki or Irako. His crush, on the other hand, became Tadanaga's concubine.
- Complete Monster: Even in a world where murder for honor is considered noble, these two manage to firmly take the very bleakest moral standpoint:
- Kogan Iwamoto is a peerless samurai and the heartless head of the Kogan-Ryuu school. When he was younger, Kogan used to show off his techniques by decapitating restrained slaves in the hopes of gaining the right to serve under the shogun family. Kogan's cruelty does not diminish even as decades go on and dementia leaves him functional for at most half a day of the year. Taking the widow of a man he killed as his favorite prostitute, Kogan considers her his property, and when another man sleeps with her, Kogan sexually mutilates both of them out of anger. Viewing his own daughter as a tool to produce a male heir, Kogan wants his best student to rape her to ensure his grandchildren will be skilled samurai, and when she steals his sword, he angrily orders his men to kill her.
- Tadanaga Tokugawa is a psychopath who uses his position as the younger brother of the shogun to terrorize his people. Regularly violating and murdering the daughters and wives of his retainers, Tadanaga is little more than a Serial Rapist and Serial Killer who is above the law. When one samurai dares to deny Tadanaga's demand to be attended by his wife, Tadanaga forces him to fight to the death against another warrior. He keeps a deformed samurai in his dungeon to rape and cannibalize women while he watches, and sends the shredded body of a girl back to her brother to mock the family. Organizing a tournament in which samurai must fight to the death using real katana instead of traditional wooden bokken, Tadanaga demands the body of one fallen warrior be humiliated by decapitation.
- Nausea Fuel: Plenty, with Kogan's death being a standout example.
- Nightmare Fuel: The after-mentioned Eye Scream.
- Squick: You will finding something about this series revolting.
- Yamazaki's autofellatio scene in the forest. God, we wish we were making this up.
- What Do You Mean, "It's for Kids"?: Yes, this ran in Champion Red, a shonen manga magazine, despite all the Squick and Gorn.
YMMV / Shigurui