Volume 4 is the fourth volume of Shigurui that includes chapters 16-20.
This volume picks up a year after events of Volume 3. Fujiki and Gonzaemon investigate the identity of a mysterious killer who has been murdering members of the Kogan-ryuu school.
There will always be one or two tyrants at any given point in history. But no matter how vicelike a tyrant was over his lands, confiscating and punishing him was not difficult in the very least. However, if the blood of Tokugawa Ieyasu himself flowed through those veins, it would be difficult to chastise him. The fortress of Tokugawa Tadanaga, son of a former Shogun and brother of current Shogun Iemitsu, was at Sunpu Castle. At the Castle one night, the young daughter of a low ranking official had been chosen to enter Tadanaga’s bed chambers to attend to his needs. The girl is bathed, combed and subjected to a meticulous series of tests to ensure she carried no weapons or messages on her person. It was not a rare occurrence for a Lord to take interest only in a noble's servant woman, but the children of commoners as well. As she enters his bed chambers, Tadanaga strangles the girl to death as his female servants look on powerlessly. Although not one person at Sunpu Castle could put an end to his tyranny, a certain battle held at Sunpu Castle involving real swords would be his downfall.
3 years since Iraku was expelled from the Kogan-ryuu school, Tadanaga had become ruler of Enshuu, resulting in many Ronin gathering to the taverns of Kakegawa hoping to service him. At a local tavern, a rowdy group of 8 Ronin who killed indiscriminately and without concern for consequences insulted the school of Kogan-ryuu. They referred to Gonzaemon as a simpleton, and Mie and Fujiki as insane. However, they are not aware that Kondou Suzunosuke, a 15 year old boy and student of Kogan-ryuu, was overhearing the conversation. In revenge, Suzunosuke swiftly kills one of the men, and as the rest of the group stand and prepare to attack Kondou, their leader Tanba Henysai orders them to stop. Later at the school, Suzunosuke has an audience with Okitsu Sanjurro, Maruko Hikobee, Yamazaki Korouemon, Munakata, Fujiki, and Gonzaemon at the head. Suzunosuke explains to Gonzaemon he had pledged a vow of a duel at Jinba pass with the Ronin. He apologises for bringing this fight to the school, promising to defeat each one. Gonzaemon commends Suzunosuke for defending the honour of the Kogan-ryuu school. Apart from Fujiki, the disciples are impressed with the tenacity of the new young student.
At Jinba pass, 6 of the 7 Ronin lie dead from single fatal strikes from Fujiki’s bare fists. Only their impressed leader, Tanba remains. Although Tanba attacks Fujiki with his sword, the latter still refuses to wield a weapon against what he considers straw dogs. Fujiki kills Tanba with ease while Suzunosuke stands in amazement, strengthened in his belief that the Kogan-ryuu school was the mightiest in the land. Suzunosuke begins to cry, hoping that one day he would become Samurai like Fujiki. Fujiki enters the dojo the next day, and though at times he envisioned Iraku on the top of the same rafters he used during his escape from Gonzaemon’s wooden sword, he discovers the decapitated head of Suzunosuke. When a body is discovered at the Kogan estate, the first suspect was not from outside but within. Gonzaemon visits Kogan, and on realising he had relapsed into his demonic state, accepted he was not the killer. The rest of the body is discovered later at a bamboo forest nearby Suzunosuke’s house. Okitsu, Maruko, Yamazaki, Munakata, Fujiki, and Gonzaemon discuss potential suspects; which would be endless, given that after the Battle of Sekigahara, the Tokugawa Shogunate brought ruin to many daimyo, leading to the sudden creation of over twenty two thousand Ronin. Starting in the first year, acts of depravity began on a nationwide scale, quickly growing beyond the ability of officials to contain. At the funeral procession, Fujiki ponders why Suzunosuke was crying on that day he defeated the Ronin. At a meeting with all disciples led by Gonzaemon, Okitsu declares that the name of Kogan-ryuu had been besmirched and Maruko considers it was too late to save, for their honour was already lost the moment Suzunosuke was killed. Gonzaemon suggests a scapegoat, someone with sufficient skill who had displayed animosity to the Kogan-ryuu in the past. Munakata (the assistant master disciple who provided Iraku with a bamboo sword during his false initiation), suggests Higaki Jingorou, a man defeated and beautified by Gonzaemon in the past. Gonzaemon agreed this would suffice. Munakata was a highly experienced swordsman and former vigilante in Kakegawa. His twenty deep scars on his iron body served as proud evidence he was a warrior of the Sengoku era Sengoku era. His scarred hands displayed strength sufficient to catch a thrown knife in mid-air. On the passing of a martial art, there existed the monetary licence, the loyalty licence, and the skill licence. The monetary licence was bestowed on anyone who provided enough gold regardless of skill. The loyalty licence was awarded by a schools’ grandmaster or those close to him, again regardless of skill. Suzunosuke’s licence had been bestowed in this manner, for his grandfather was an old friend to Kogan. Only a skill licence was granted based on the actual martial prowess of the receiver. Munakata held such a licence.
Higaki did not flee Kakegawa but resided on Mt. Awaga to train in the ways of the sword. At night, Munakata travels there and easily kills Higaki in a duel. As Munakata heads back to the village, he stands before what appeared to be a blind man standing on a bridge within the mist, smiling madly and leaning against a cane. Munakata, realising the cane was a sword, is astonished that the killing intent infused throughout his body made it clear it was a attacking stance so bizarre no one from any school had seen or heard of. Munakata realised this was Suzunosuke’s true killer, but is quickly killed by the swordsman. Later, villagers discover Munakata’s decapitated head on the bridge, biting down on a bamboo sword.
The students observe Munakata’s body and to their dismay, he was sliced in half via an upwards strike. They deduce Munakata must have let his guard down, and Gonzaemon warns all disciples to stay alert, for a person able to defeat Munakata would require a swordsman of tremendous skill. At an eatery in Kakegawa, two men discuss Munakata’s death. One of them mused the bamboo sword was perhaps a message that Kogan-ryuu was as blunt as a bamboo. Before completing his sentence, Yamazaki, overhearing, murders them both with his fist. Later on the street, a local villager wielding a sword seeks vengeance; but is killed when Yamazaki strikes him with his fist, inadvertently dislodging the villager’s eyeball out of its socket. To the disgust of the villagers nearby, Yamazaki retrieves the eyeball and eats it. Gonzaemon and Maruko discuss Iraku’s past, while Mie’s appears mysteriously behind in the shadows. Gonzaemon wishes her to get well, confirming Mie has not been at a correct state of mind since Iraku’s exile. Ten days after Suzunosuke’s death, though Gonzaemon had forbidden anyone from leaving the estate after dark, Yamazaki heads to the woods. Leaning against a tree, Yamazaki, in tears, performs autofellatio while fantasising about Suzunosuke. Soon after, the true killer appears and easily kills Yamazaki, his Nagare insufficient against the speed of the killer’s attack. Later, Yamazaki's severed head is discovered burned as though a pair of heated tongs had been held against his face.
Fujiki informs Gonzaemon Iraku is the killer. Suzunosuke’s head was laid at the very place that Iraku fled to on the day he arrived. Three years ago, Munakata handed him a bamboo sword before his punishment, and Munakata was found with a bamboo sword in his mouth. Yamazaki also presented burning tongs to Iku later that day, and had one side of his face seared. The group deduce that Iraku had resurfaced, and was residing somewhere in Kakegawa. Maruko and Okitsu visit Tsudanoichu, a blind masseuse and acupuncturist. Maruko asks Tsudanoichu if any new blind strangers had appeared in Kakegawa recently, given blind people surely had contact with one another. Tsudanoichu mentions Toudouza, an organisation composed of and governed completely by the blind. Encompassing all men in the land who were without sight, its scale was far larger than anyone could have imagined. The Toudouza was composed of four divisions, fourteen subdivisions, and 73 sub sections. Tsudanoichu suggest they speak to a man called Shizuhata Kengyou, the head of the Toudouza. Kengyou was a possessor of lands on par with any nobleman, and with no less than 13 personal man servants, he enjoyed a life of incredible luxury. The one to bestow such prestige to the leader of Toudouza, was none other than Tokugawa Ieyasu himself. Maruko took insult that Tsudanoichu could so casually suggest that the disciple of a mere martial arts master could request a meeting with him. As punishment, Okitsu torments the blind man with excruciating sounds he had not heard of. Later, Maruko and Okitsu part ways as Maruko visits a local bathhouse. Despite handing in his weapon at the check in counter, the strength of the body of Maruko was second only to Gonzaemon himself. As Maruko prepares to sit in the bath, within an instant, Maruko is sliced in half by Iraku.
Inside Maruko’s mouth was his own penis. Rumours began to spread this was not the work of a man but that of a demon. In the tiger’s room, a chamber set aside for students who lived at the estate, sat Fujiki and Okitsu. While Fujiki writes, Okitsu recalls those who had died and noted to Fujiki that the room has now become too large. Fujiki was taught how to write by Okitsu; but struggles as the fist he had used against the Ronin had become infected. The next day at the Shizuhata Kengyou’s Estate, below Kakegawa Castle, at a space sprawling nearly 50 thousand square feet, sat Kengyou’s secretaries. These men were not blind and sat before them was Okitsu, who was presented with three gold bars. One for each tiger (excluding Suzunosuke) as reward for revealing the precise time each Kogan-ryuu disciple would be most vulnerable. The secretaries asked when the remaining three tigers, Kogan, Gonzaemon and Fujiki, would be next. Okitsu stated it would take a while longer given those tigers were not as easy to kill. Okitsu did not mention Fujiki is vulnerable due to an infected hand, although even he himself could not say why. As Okitsu leaves, he scouts the area, and then proceeds into the woods. Fujiki calls his name and asks if Iraku is at Shizuhata Kengyou’s estate. Okitsu ignores the question, and queries whether the Kogan-ryuu has a future. Fujiki’s responds that it lies with Mie. Okitsu scoffs, proclaiming once the heart was broken, it could never be mended. Okitsu commences to attack Fujiki, mimicking the technique Fujiki discovered against the Funaki assassin and used against Iraku. Despite completing the manoeuvre, Okitsu’s hand is cut off. Okitsu is impressed that Fujiki defended against his own secret technique and commends him. As Fujiki delivers a killing blow, Okitsu tearfully holds Fujiki’s hand, while Fujiki recalls his childhood as it was Okitsu who had taught how him to write. Fujiki noted that the tiger’s cub would truly become even larger now.