Kushimaru Kuriarare

was a Kirigakure jōnin and a member of the founding generation of the Seven Ninja Swordsmen of the Mist wielding the deadly blade Nuibari.

Background
In the anime, according to Kakashi Hatake, Kushimaru committed many acts of cruelty in his lifetime, killing his sensei being one of them.

At some point in time, Kushimaru encountered the young Might Guy, Ebisu and Genma Shiranui on a mission alongside the other members of the Seven Ninja Swordsmen of the Mist. The young shinobi managed to flee, however, due to the timely arrival of Might Duy who sacrificed himself in order to save the genin.

Personality
In the anime, Kushimaru was shown to revel in killing like his other swordsmen team-mates, taking pleasure in crucifying countless shinobi. He is also noted to have committed many cruel acts such as killing his sensei. He also had a penchant for laughing maniacally. Kushimaru does not take kindly to anyone outside the Seven Ninja Swordsmen of the Mist wielding one of their swords and resolved to reclaim the Kubikiribōchō from Kakashi. He also tended to argue a lot with Jinpachi Munashi, his fellow comrade. The two swordsmen collective cruelty earned them the nickname from Kakashi.

Appearance
Kushimaru was very thin and tall in stature, which gave him an overall gangling appearance. He had long, shaggy, straw-coloured blond hair and his face was concealed by a white, porcelain Anbu mask, with a green-coloured triangle on its lower half, slits for eye-holes and Kirigakure's symbol etched into the top. His attire consisted of a sleeveless black shirt, matching pants, complete with a waist-guard, and Kirigakure's striped wrist and leg-guards. He also wore bandages around his neck like the other members of his generation of the swordsmen.

Abilities
As one of the Seven Ninja Swordsmen of the Mist, Kushimaru was one of the most powerful shinobi Kirigakure ever produced. His generation of swordsmen was even noted to be the strongest in the village's history. He was capable of using the Silent Killing technique, as seen when fighting the Third Division of the Allied Shinobi Forces while under the cover of his former colleague Zabuza Momochi's Hiding in Mist Technique.

Kenjutsu
Kushimaru wielded the unique longsword Nuibari. With it, he was not only able to precisely pierce multiple enemies in quick succession, but also stitch them together utilising a substantial length of wire attached to the blade. This aptly demonstrated his proficient dexterity while handling this particular needle-like sword, as he was able to repeatedly catch it securely just mere moments after previously forcing the blade through his adversaries.

In the anime, he was seen using senbon and setting a trap for his opponents by hiding his wire strings underground to form a complex structure, that cuts off the opponents feet. He could also use a technique that would kill the enemy slowly and painfully.

Fourth Shinobi World War: Confrontation
Amidst the battle with the Third Division, the reincarnated previous generation of the Seven Ninja Swordsmen of the Mist are summoned by Pakura and Gari, under Kabuto Yakushi's instruction, with the intention of overwhelming the opposition. Amongst their number is Kushimaru, who after being futilely bombarded by various techniques, retrieves Nuibari from within a scroll in Mangetsu Hōzuki's possession. Entering the fray whilst concealed by a thick mist, Kushimaru begins a silent massacre, impaling a multitude of shinobi before bundling them together. With Zabuza Momochi's defeat, the mist clears, exposing Kushimaru to the enemy.

In the anime, his sealing is expanded upon. When dawn broke on the war's second day, Kushimaru reappeared on the battlefield as he and Jinpachi Munashi went on a killing spree until Kakashi intercepts them. Upset with an outsider wielding the Kubikiribōchō, Kushimaru decides to reclaim the sword from Kakashi, resulting in a bicker with his fellow swordsmen. The swordsmen taking advantage of their immortality to overwhelm Kakashi until Might Guy backs him up. The Konoha shinobi's teamwork and his constant arguing with Jinpachi proves his downfall.

Fourth Shinobi World War: Climax
In the manga, it was only noted that Kushimaru and the other reincarnated shinobi being dealt with by the Third Division were sealed away before Kakashi and Might Guy departed for Naruto Uzumaki's location. Later, with the release of the Impure World Reincarnation technique, a light of sorts encased Kushimaru's sealed body as the technique was dispelled and his soul was returned to the afterlife.

Trivia

 * roughly means "skewer", and means "chestnut hail"; like all members of the Seven Ninja Swordsmen, his surname is derived from a type of produce.
 * During his debut in the anime, Kushimaru's eyes are visible.