Kurotsuchi

is a kunoichi from Iwagakure.

Background
In the anime, a young Kurotsuchi witnessed Deidara flee from Iwagakure, shortly after bombing surrounding buildings. At the time, Deidara had already become part of Akatsuki.

Personality
Kurotsuchi is generally calm and easy-going. She has displayed a powerful loyalty to her village, as she was more interested in killing the jinchūriki of the Eight-Tails and Nine-Tails than actually protecting them. She decided this was the best plan so Iwa could become stronger than Konoha and Kumo.

Like her grandfather, Ōnoki, she is very audacious. She often sarcastically implies that because the Tsuchikage suffers from back pain he should be replaced by someone younger. She also has an immature side to her, which she hides, as seen when she reprimands Akatsuchi on his childish excitement about flying when they were heading towards the Island Turtle, though she was secretly excited about the prospect as well.

Kurotsuchi has the utmost confidence in her skills, as seen when battling and capturing Kabuto. This trait makes her somewhat arrogant of her abilities, which she seemingly inherited from her grandfather.

Despite Deidara being a member of Akatsuki, she holds respect for him, calling him "Deidara-nii"(Big Bro Deidara or Bro in the english sub). While there is no known kinship between them, it is implied that she only does this as a sign of respect. In the anime, she even stated that they were once close friends,until his defection from Iwagakure.

Appearance
Kurotsuchi has short, black hair and pupil-less, pink eyes (depicted as black in the anime) and are accentuated by her eyelashes running upwards at the corners. She wears the standard attire of the Iwa-nin consisting of a red uniform with her right sleeve missing and a lapel over her right leg, the brown Iwagakure flak jacket, fishnet tights and a skirt over them. She also wears regular shinobi sandals and a pair of gloves.

Abilities
Kurotsuchi is a highly capable kunoichi, having been chosen to guard the Third Tsuchikage during the Kage Summit, and the reinforcement of the Island Turtle. She can be quite deceptive in combat, as demonstrated when she told her team-mates that she would send Kabuto in their direction, only to have him jump in the other direction falling into her trap.

In the anime, she is also revealed to be skilled in kenjutsu as well as taijutsu defeating several of Naruto's shadow clones. She also displayed great evasiveness as well as sharp reflexes as seen against Ganryū and the other Kiri-nin under his command.

Nature Transformation
Kurotsuchi is capable of using three basic nature transformations. One is Earth Release which enables her to erect a protective rock dome that was sturdy enough to endure several tons of rock falling on it. She can also use Earth Release to unearth things underground. Kurotsuchi can combine the basic natures she can manipulate to create an advanced one. Combining fire and earth natures to create Lava Release, which in her case, creates quicklime. She can use Lava Release: Quicklime Congealing Technique to cause corrosive damage, and combine it with Water Release: Water Trumpet to increase its range and cause it to harden to trap the opponent.

Five Kage Summit Arc
Kurotsuchi and Akatsuchi escorted the Third Tsuchikage to the Five Kage meeting. When they were leaving the Tsuchikage hurt his hips trying to carry his own luggage, so she suggested that he should retire. Despite this, they managed to arrive at the Land of Iron without further incidents. During the meeting, she came to the Tsuchikage's defence during the Fourth Raikage's outburst.

When Kurotsuchi heard that Sasuke Uchiha had infiltrated the meeting, she asked for permission to fight the man who defeated Deidara. The Tsuchikage agreed, but told her to keep out of the Raikage's way. She watched Sasuke's battle from the shadows and, when Sasuke caused the room to collapse, she created a dome to protect herself from falling debris. She also fended off Zetsu's Spore Technique. While leaving the Land of Iron, she suggested to the Tsuchikage that they eliminate Killer B and Naruto so they can foil Madara Uchiha's Eye of the Moon Plan and weaken Konohagakure and Kumogakure. When he disagreed, she exclaimed that he wasn't acting like the stubborn old man she knew of. He responded that he remembered who he was before he became a "hard-headed old man".

Upon their return to Iwagakure, they receive approval from the Earth Daimyō to continue on with the shinobi alliance. After Akatsuchi had informed Kurotsuchi about their encounter with Madara Uchiha, she mocks her grandfather by comparing his age to Madara's. She later shares her thoughts on the upcoming war, finding it unimaginable.

Confining the Jinchūriki Arc
Upon returning to their village, they were informed that the Earth Daimyō has approved the formation of the Allied Shinobi Forces. She and Akatsuchi then joined Ōnoki to reinforce the garrison on the Island Turtle, before spotting and attacking Kabuto Yakushi and Deidara. After Ōnoki drew Deidara away to avoid damaging the turtle, she battled Kabuto and managed to trap him so that he could be interrogated by Aoba. However, Kabuto later freed himself by reverting into his snake-like form, claiming that knowing about Kurotsuchi's techniques beforehand had aided him in his escape. Knowing Kurotsuchi's techniques also helped him in lowering everyone's guard, giving him an opportunity to capture Yamato. Kurotsuchi chased after Kabuto, but Kabuto was able to hide in Manda II's nose and released the Summoning Technique, vanishing along with the giant snake.

Shinobi World War Arc
After escorting the Island Turtle back to Kumogakure, she is assigned to the Second Division of the Allied Shinobi Forces, unhappy with the fact that her father was her commander. Later on she used Earth Release: Opening Earth Rising Excavation with her father to unearth the White Zetsu Army and starts fighting them. After a long fight with the Zetsu Army, she retreats along with her division and the members of the Fifth Division so they can backup Darui's division.

In the anime, Kurotsuchi later visited the Fifth Division to speak with Deidara. She is later escorted by Okisuke to where Deidara was. While she interrogated Deidara about Kabuto Yakushi's whereabouts, she brings up the fact that Sasuke Uchiha was still alive and is a member of the Akatsuki which shocked Deidara who believed he had killed him. Kurotsuchi becomes annoyed by Deidara's lack of co-operation Deidara is giving and asks if the White Zetsu Army clone impersonating a Samurai could open Black Ant so she could speak to him. Before he could do so, news reaches the division of the impersonators within their ranks which leads Okisuke to question the samurai in front of him. Giving the wrong answer, the samurai is cut down mercilessly but Deidara still manages to escape. While chasing Deidara, Kurotsuchi is later trapped in the Hiding in Frost Technique cast by Chūkichi but he is quickly summoned away by Kabuto. Kurotsuchi, Kankurō and the Fifth Division soon caught up to Deidara and realise that he has planted land mines underground and reacted by using Lava Release: Quicklime Congealing Technique to stop the land mines from exploding once she touched the ground, Deidara then exploded and escaped once again. Kurotsuchi transforms into Sasuke Uchiha and finds Deidara and leads him off into a trap and re-seal Deidara inside Black Ant again and Kurotsuchi leaves.

Video Games
In Naruto Shippūden: Ultimate Ninja Storm Generations, Kurotsuchi is a support-only character.

Trivia

 * means "Black Earth".
 * Before the Second Naruto Fanbook, many fans were not sure as to Kurotsuchi's gender. However, the fanbook confirmed that she was in fact female.
 * Kurotsuchi refers to Deidara as "Deidara-nii" (an honourific meaning "big brother"), which may mean that Deidara is of some relation to her, or it's used as a sign of respect.

Quotes

 * (To Ōnoki)
 * (To Deidara while transformed into Sasuke)"Bro,Lightning Release isn't your weakness,(dispels transformation)it's your stupid obsession with art!"