After the death of Oboro Shirakumo, his body was recovered by All For One and taken to Daruma Ujiko, who combined various quirks to create the Nomu called Kurogiri. All For One tasked Kurogiri with aiding and overseeing the development of Tomura Shigaraki.
Kurogiri appears at the Unforeseen Simulation Joint, using his Quirk to warp himself and the villains to the area. He then appears before the escaping class of students, introducing themselves as the League of Villains and revealing that they were the ones who broke into U.A. High School the previous day.
He goes on to say that their mission is to kill All Might and wonders why he isn't here. Katsuki Bakugo and Eijiro Kirishima attack Kurogiri, but their attacks simply go through him. He then uses his Quirk to warp most of the students to various areas of the USJ.
After doing this, Kurogiri fights Thirteen. Kurogiri uses his Quirk against Thirteen's Quirk by warping Thirteen's Black Hole against her. As Thirteen's Quirk starts turning her to dust, Kurogiri says that Thirteen's battle experience is far lower than other heroes due to her only specializing in disaster relief. Having incapacitated Thirteen, Kurogiri tries to stop Tenya Iida from escaping, knowing that Tenya's escape would put the League of Villains in jeopardy, but is intercepted by Mezo Shoji.
As Tenya reaches the exit, Kurogiri tries to attack him again, but Ochaco Uraraka, seeing a physical part of him, is able to grab him and use her Zero Gravity to make him float into the air, stopping him with the help of Hanta Sero and Rikido Sato. After being flung into the air, Kurogiri decides to warn Tomura and warps himself away. He appears before Tomura Shigaraki, and informs him on the situation, telling him that he has incapacitated Thirteen but failed to stop one of the students from escaping, much to Tomura's frustration. Realizing that the escaped student will most likely go and find dozens of Pro Heroes whom they won't be able to defeat, Tomura decides to retreat, but not before killing the remaining students.
Shigaraki and the Nomu attack Izuku, Tsuyu and Mineta, but before they have a chance to hurt them, All Might arrives at the scene. Tomura decides to continue their mission. All Might starts by striking Nomu, but the creature absorbs the impact. All Might figures that he can wear Nomu down, and uses a powerful reverse suplex to smash Nomu into the ground. However, Kurogiri intervenes, using his Quirk to save Nomu and allowing Nomu to turn the tables on All Might. All Might sends half of Nomu's body through a portal while he still remains in the suplex position. Nomu uses the opening to grab onto All Might's weak point, while Kurogiri slowly drags him into the warp gate, to carry out his duty to eviscerate All Might.
Alert to All Might's peril, Izuku rushes over to aid him. Kurogiri cuts Izuku off and prepares to warp him away, but Katsuki appears and strikes Kurogiri and pins him down, preventing him from using his Quirk. Kurogiri is then set free when Nomu attempts to attack Katsuki. Knowing that his powers are declining rapidly, All Might engages Nomu in a ferocious fist fight. All Might decides to surpass his 100% after seeing that his attacks are having minimal effect. All Might launches a devastating punch against Nomu, sending Nomu flying out of the U.S.J., defeating him.
After All Might defeats Nomu and Tomura starts to panic, Kurogiri calms him down by saying that Nomu did considerable damage to All Might and they should take the opportunity to finish the job. After Tomura regains his composure, he and Kurogiri attempt to attack All Might, but they are intercepted by Izuku Midoriya, which gives the heroes enough time to arrive at the USJ, in turn forcing Tomura and Kurogiri to stop their attack. They are then sucked into Thirteen's Black Hole and are seemingly turned into dust, but Kurogiri uses his Quirk at the last second to warp him and Tomura back to their hideout, thus saving themselves from being killed. After the mysterious voice on the monitor asks about the whereabouts of Nomu, Kurogiri regretfully reports that they do not know Nomu's coordinates due to him being thrown far away and were unable to pinpoint his location, thus being unable to retrieve him.
Kurogiri appears before the hero killer, Stain, who draws his katana and aims it at Kurogiri. Kurogiri tells Stain to withhold his blade as they have similar interests and that he has been wanting to meet someone of his notoriety. Kurogiri then asks Stain for a moment of his time, teleporting them both away.
Kurogiri brings Stain to the League of Villains hideout to meet with Tomura. However, the meeting between Stain and Tomura goes awry. Kurogiri asks the mysterious voice on the monitor if it is all right to keep the meeting going, but the voice orders Kurogiri to allow them to continue, saying that Tomura's meeting with Stain (an experienced infamous villain) will stimulate Tomura's growth.
The meeting between Tomura and Stain turns into a fight. Kurogiri tries to intervene, but Stain injures him and prevents him from moving. After Stain and Tomura declare their common interest in destroying the current society, Stain restores Kurogiri's mobility and demands to be returned to Hosu.
Kurogiri warps himself, Stain, and Tomura to Hosu. After Stain leaves to finish his business, Tomura complains about Stain's constant preaching, to which Kurogiri replies that he shouldn't mock Stain for his preaching and states that Stain's villainous methods have produced great results, which intrigues Tomura. Tomura orders Kurogiri to release the Nomus. Kurogiri warps three Nomus to their location, and Tomura orders the Nomus to attack Hosu.
Kurogiri asks Tomura if he will join the assault on Hosu. Tomura replies that he won't because of his shoulder injury.
Tomura, using binoculars, watches Stain kill the winged Nomu and becomes annoyed that nothing is going his way. After the other two Nomu are restrained and arrested, Tomura disintegrates his binoculars out of anger. Tomura decides to leave and return to the League of Villains hideout. Kurogiri asks Tomura if the results of the attack on Hosu are to his satisfaction, but Tomura replies that the results depends on tomorrow. Kurogiri teleports himself and Tomura back to the League of Villains hideout.
When Giran brings in two candidates to join the League of Villains. Tomura becomes displeased with his visitors due to them seemingly being types he despises the most and orders Kurogiri to send them away. Kurogiri asks Tomura to be patient and listen to what the visitors have to say because they were scouted by the broker who produces quality results. The Broker tells Kurogiri that he wants his service charge one way or another; The Broker also agrees with Kurogiri about letting them introduce themselves.
After Himiko Toga and Dabi introduce themselves, Tomura becomes angry at them for talking about Chizome, and prepares to attack them. As the three clash, Kurogiri uses his Quirk to stop the fight. Telling Tomura that expansion is necessary in order to achieve his wishes, now that the spotlight is on them. He asks him to not reject help. Reminding Tomura if he doesn't make use any of the offered help, everything left to them will disappear.
Understanding Kurogiri, Tomura storms out of the room. The Broker comments about Tomura being too young; Kurogiri asks the broker to wait a few days for their reply regarding Dabi and Himiko's registration; he comments that Tomura understands what needs to be done and he is sure he'll understandingly accept them.
After finding his own convictions to achieve his goals, Tomura decides to organize an operation to kidnap Katsuki Bakugou with the new recruits of the League of Villains, the Vanguard Action Squad. At the League of Villains’ hideout, Kurogiri wonders if the Vanguard Action Squad will be able to handle the mission. Tomura assures Kurogiri that they will be fine; Tomura decides that it is not time for him to reappear and begins to comment on his gameplay. Tomura realizes that his gameplay was faulty when he first attempted to murder All Might and now has decided to let his pawns take down the ones up high before aiming for the final boss.
Tomura explains that he intends for the Vanguard Action Squad to make a crack in the superhuman society, noting that the Vanguard Action Squad’s endeavors at Class 1-A and 1-B's training camp will be a blow for the Pro Heroes whether they succeed or not. Kurogiri questions if the Vanguard Action Squad means nothing to him, but Tomura rebuffs Kurogiri’s claim, saying that he respects the Vanguard Action Squad’s strength and personally hopes they succeed, Tomura continues to say that while they have their differences, they can rely on each other because both he and Kurogiri are not the only ones oppressed by society’s rules.
Kurogiri arrives at the training camp in order to retrieve Spinner and Magne. After doing so, Kurogiri travels to the Vanguard Action Squad's rendezvous point and blocks Izuku, Mezo and Shoto with his black mist. While blocking the young Heroes, Kurogiri warps Himiko, Twice and the Noumu away from the training camp. After Mr. Compress deactivates his Quirk, which frees Fumikage and Katsuki, Kurogiri warps Mr. Compress, Dabi and the captured Katsuki away from the training camp.
After warping most of the Vanguard Action Squad back to the League of Villains' hideout, Kurogiri is present when Tomura talks to the restrained Katsuki.
Katsuki attacks Tomura and knocks off the hand on his face. Kurogiri attempts to rush to Tomura in order to calm him, but Tomura fiercely glares which stops Kurogiri. Tomura asks the Vanguard Action Squad and Kurogiri to let him handle Katsuki.
Tomura orders Kurogiri and Mr. Compress to knock out Katsuki. Suddenly, All Might breaks in with Kamui Wood swinging in and restrains Kurogiri along with the other League of Villains with his Lacquered Chains Prison. Tomura orders Kurogiri to warp all the Nomus to them. However, Kurogiri isn't able to warp the Nomus because they are no longer near the portals.
Refusing to let the pro heroes win, Tomura orders Kurogiri to create portals. However, Kurogiri is knocked unconscious by Edgeshot who used his Quirk to enter Kurogiri's body and knock him out from the inside.
Out of nowhere, Nomus appear from mysterious back liquid which takes the pro heroes off guard. The unconscious Kurogiri along with the League of Villains and Katsuki Bakugo are teleported by the mysterious black liquid to the League of Villains' destroyed warehouse where All For One is. Before they can flee, All Might quickly arrives at the place and fights against All For One, while the rest tries to flee, capture Katsuki again and run away, but fail when Izuku, Eijiro and Tenya manage to rescue Katsuki.
Understanding that they have lost, All For One uses his Forced Quirk Activation to activate Kurogiri's Warp Gate, thus creating a portal for the League of Villains to escape through. Before Tomura can attack Gran Torino, he along with the Vanguard Action Squad is magnetically pulled into Kurogiri’s Warp Gate. The Vanguard Action Squad are forcefully sucked into Kurogiri's Warp Gate and is teleported away. As he is being sucked into the Warp Gate, Tomura calls out to his teacher concerned for his safety. Before Tomura teleports away, Sensei tells Tomura to continue the fight. Tomura and the unconscious Kurogiri are teleported away by the Warp Gate, causing the portal to disperse.
After an intense fight against All Might, All For One is defeated and imprisoned in Tartarus. His loss weakened the League of Villains considerably, and now, under Tomura's command, they try to reorganize and regain strength. Kurogiri remembers that All For One told him about a "power" he left behind that he could use to protect Tomura if he was caught or killed. Kurogiri explains it to Tomura and asks him for permission to retrieve that power for him. Tomura agrees.
During the battle between the Pro Heroes and the Shie Hassaikai, Gran Torino and Naomasa Tsukauchi have managed to track down and find Kurogiri with the help of eyewitness reports and have him subdued. Gran Torino tells Kurogiri that if they arrest him, the League of Villains will fall apart.
As Naomasa warns Gran Torino about Kurogiri's Quirk, Kurogiri asks Gran Torino if he knows of the rumors about a "wild man" appearing in the mountains where they are at. Kurogiri says he has business with the "wild man". Gran Torino would prefer Kurogiri to tell him all about it behind bars.
Suddenly, a huge noise reverberates in the area which catches Gran Torino's attention. An enormous beastly man that towers over trees appears with a radio around his neck, which surprises Gran Torino. Kurogiri states that the wild man is one of All For One's faithful servants: Gigantomachia.
Gran Torino took Kurogiri into police custody at the cost of allowing Gigantomachia to escape.
After being captured by Gran Torino and the detective Naomasa, Kurogiri was sent to Tartarus. Once there he show no sign of confessing or disclosing anything about the League of Villains, but they learn that the base of his Quirk resembles that of Oboro Shirakumo’s Quirk Cloud.
Shota Aizawa and Hizashi Yamada are called to Tartarus and informed of what has been found about Kurogiri. They explain that he is unconscious because otherwise, he would activate his Quirk. Shota uses his Quirk as Kurogiri comes too. Hizashi notes that the mist still won’t dissipate from Kurogiri’s face. Kurogiri notes that it had been awhile since he has visitors and recognizes Shota from the U.S.J. Incident. He then asks about Tomura and wonders where he is and if he has been captured. Shota observes that Kurogiri really cares about Tomura, and Kurogiri says it is his duty to care for him. Shota remember how Oboro would also take care of others and Kurogiri wonders what he is talking about as Shota takes off his goggles and cries out to Oboro, with tears in his eyes, saying if he is still in there somewhere, then the three of them will become heroes together.
Shota continued to speak to Oboro inside of Kurogiri. Kurogiri denied knowing what he was talking about and said he was Kurogiri, but suddenly Oboro was able to break through Kurogiri’s mist, and hint at a hospital before Kurogiri fell unconscious.