Atsuhiro Sako

Atsuhiro Sako (迫圧紘), also known as Mr. Compress (コンプレス), is a villain affiliated with the League of Villains and a member of the organization's Vanguard Action Squad. He is known for being one of the smartest villains in the world and acts as the brains of the League of Villains. He and the rest of his team serve as the main antagonists of the School Trip Arc.

Appearance
Atsuhiro's face is covered by a smiling mask. He wears gloves, a large and fancy overcoat, boots, and a top hat with a feather.

In the Hideout Raid Arc, he wears a different mask.

Personality
Atsuhiro is a talkative, humorous person with his allies and enemies alike. He seems to value the possibility of choosing one's beliefs, insisting that U.A. High's students have had their values hammered into them by others. Although he claims to be good at running away, he expressed disappointment in the abilities of the Hero cadets he met. He also trusts his own judgment, kidnapping a second target beside the one he was assigned to.

History
At some point of his life, Atsuhiro worked as an entertainer.

School Trip Arc
Atsuhiro appears on a tree branch and reveals that he used his "magic" to take Katsuki Bakugo by turning him into a marble. Atsuhiro states that the Heroes do not deserve someone of Katsuki's caliber and notes that Katsuki will shine even brighter on the villains' side. Izuku Midoriya demands that he give Katsuki back.

The Bakugo Escort Squad, Ochaco Uraraka, and Tsuyu Asui come face to face with Atsuhiro who has kidnapped Katsuki. Izuku demands that he gives Katsuki back because he would never work with villains due to being his own person. Shoto Todoroki freezes the tree but Atsuhiro evades Shoto's attack. Atsuhiro states that they are attacking the training camp to make a point, that they are proving there is not only one perspective at which to look. Atsuhiro criticizes the U.A. students' for having their perspectives and values chosen for them, displeased that there is no free will. Mezo Shoji realizes that Fumikage Tokoyami has also been taken. Shoto surmises that the villain sneaked up behind them and kidnapped Katsuki and Fumikage. Atsuhiro explains that his mission was to capture only Katsuki, but after seeing Fumikage overpower and defeat Moonfish so easily, he decided to kidnap Fumikage as well because of his powerful Quirk and notes that he will prove to be useful. Shoto hands Kosei Tsuburaba to Ochaco. After doing so, Shoto uses his Giant Ice Wall attack in an attempt to immobilize Atsuhiro. However, Atsuhiro evades and apologizes for only running away and deceiving, admitting that is what he is good at. Atsuhiro informs the Vanguard Action Squad that their target has been captured; he tells his fellow villains that the mission is done and states that they have five minutes to rendezvous at the "collection point." Shoto refuses to allow them to succeed in their mission and prepares to chase after him.

Atsuhiro begins escaping and is unimpressed with the Hero cadets. Suddenly, he sees Izuku, Mezo and Shoto flying towards him. After Ochaco deactivates her Quirk, Izuku, Mezo and Shoto land on top of Atsuhiro and smash him into the ground near the Vanguard Action Squad's rendezvous point.

Dabi asks Atsuhiro to dodge and launches his flames. Atsuhiro uses his Quirk to compress himself to dodge the flames while Mezo and Izuku are injured by Dabi's flames. As Twice and Himiko Toga deal with Izuku, Mezo and Shoto, Atsuhiro decompresses himself and approaches Dabi, preparing to give the captured Fumikage and Katsuki to him. However, he searches his pocket and is unable to find the marbles containing the targets; Mezo reveals that he took the marbles from Atsuhiro immediately after they landed on the ground. Dabi calls Atsuhiro a fool, but the magician calmly tells him to wait and see what happens.

Soon, Kurogiri arrives to retrieve the Vanguard Action Squad. After Himiko, Twice, and Nomu teleport away, Dabi and Atsuhiro also prepare to leave, although Dabi is distressed that they do not have Katsuki. However, Atsuhiro relieves Dabi's concern by revealing that the compressed Katsuki and Fumikage were in his mouth all the time and the marbles Mezo stole were Shoto's compressed ice. Atsuhiro puts his mask back on while explaining that he wanted to give the young Heroes a sense of false hope and is satisfied by it as well as his flaunting which he considers a bad habit. Atsuhiro slowly enters Kurogiri's portal after bidding farewell. Having overheard what is happening, Yuga Aoyama takes action and fires his Navel Laser at Atsuhiro's face, which breaks his mask and causes him to spit out the marbles containing Fumikage and Katsuki.

After grabbing Katsuki's marble form, Dabi orders Atsuhiro to deactivate his Quirk, which frees Fumikage and Katsuki. Atsuhiro, Dabi and the captured Katsuki teleport away from the training camp.

Hideout Raid Arc
After watching the video clip about U.A.'s public apology, Tomura understands why society is criticizing U.A. for their failure and that is because the current Hero society is not just. Spinner agrees that the current Hero society is not just since the modern Heroes are only doing their job for compensation and not out of selflessness. Tomura explains that the League of Villains are fighting for a just society and intends to win this battle. Tomura orders Dabi to remove Katsuki’s restrains, although Dabi is unsure since Katsuki might attack; Tomura wants to treat Katsuki as an equal and is aware that Katsuki knows he has no possibility of winning. Dabi has Twice remove the restrains. As Twice removes the restrains, Atsuhiro apologizes to Katsuki for forcibly kidnapping him and explains that the League of Villains are not just a group of hoodlums perpetuating crimes nor did they casually abduct him; he goes on by saying that everyone in the League of Villains is shackled by the current society and hopes that Katsuki understands their discrimination.

Katsuki’s restrains are removed. As Tomura approaches Katsuki, Katsuki attacks Tomura with his Explosions. Katsuki tells the League of Villains that it is pointless to try and make him change his mind as he has already been won over by the way All Might looks when he wins. Katsuki says that from the beginning he has dreamed of becoming a Hero and surpassing All Might and nothing they say will change that.

Katsuki tries intimidating his captors, but Atsuhiro along with the rest of the Vanguard Action Squad are not intimidated; Atsuhiro states that if Katsuki was moronic, he would have listened to them and is disappointed in Katsuki's decision to go against them.

Tomura orders Atsuhiro to use his Quirk on Katsuki again. Atsuhiro is impressed with Katsuki's stubbornness. Before he has the chance to, All Might breaks in with Kamui Wood swinging in and restrains Atsuhiro along with the other League of Villains with his Lacquered Chains Prison. Atsuhiro realizes that U.A.'s public broadcast apology was just a diversion to catch him and his fellow villains off guard.

Out of nowhere, Nomus appear from mysterious back liquid which takes the Pro Heroes off guard. Atsuhiro along with the League of Villains are teleported by the mysterious black liquid to the League of Villains' destroyed warehouse where All For One is.

All For One forcefully activates Kurogiri's Quirk which creates a portal for the League of Villains to escape through. Atsuhiro uses his Quirk on the unconscious Dabi and tells Tomura that they need to leave. Seeing that Katsuki won't go with them willingly, Atsuhiro along with Twice and Himiko battle Katsuki but Katsuki fends them off with Explosions.

After Katsuki is rescued by Izuku, Tenya and Eijrou, Atsuhiro along with Kenji and Spinner hatch a plan to recapture Katsuki. Kenji magnetizes Atsuhiro and Spinner pushes him, causing Atsuhiro to fly at Izuku's group. Suddenly, Mount Lady uses Titan Cliff and intercepts Atsuhiro, which causes them to smash into each other, preventing Atsuhiro from getting to the students. Atsuhiro falls to the ground and becomes unconscious due to Mount Lady's attack.

Atsuhiro along with Tomura and the Vanguard Action Squad are forcefully magnetized by Kenji's Quirk courtesy of All For One; Atsuhiro is sucked into Kurogiri's Warp Gate and teleported away.

Internship Arc
Overhaul enters the League of Villains hideout, but is unimpressed with Tomura and his members as well as his unclean hideout. Overhaul explains to the League of Villains that with All For One's downfall, someone will eventually become the next ruler of the underworld. However, Tomura replies that he will become the next underworld ruler after he gather more members and crush the current Hero society. Overhaul asks Tomura if he has a plan, to which Tomura responds that he thought Overhaul wanted to join them. Overhaul is disappointed that Tomura doesn't have a plan to achieve his objective and laments that he wasted the potential of Stain, Muscular and Moonfish. Overhaul reveals that he wants the League of Villains to join him so that he can teach them the proper way to run an organization and use them to gain financial capital so that he can get one step closer to becoming the next underworld ruler.

As Tomura orders Overhaul to leave, Magne rejects this proposal and magnetizes Overhaul, bringing him into Magne's range. Magne hits Overhaul on the head with his weapon, to which Overhaul responds by touching Magne. Overhaul's physical contact causes Magne to blow up, much to the League of Villains' shock. Overhaul blames the League for throwing the first punch and dislikes the blood running down his face. Atsuhiro charges forward and touches Overhaul but his Compression Quirk does not activate due to being shot in the arm. Overhaul is enraged that he has been touched and severs Atsuhiro's left arm by blowing it up. Furious, Tomura dashes to Overhaul and prepares to disintegrate him. Overhaul calls for a human shield. Tomura touches Overhaul's subordinate instead which causes Tomura to disintegrate the subordinate.

Suddenly, Overhaul's subordinates crash in. Seeing that both of their organizations have suffered casualties with the deaths of their respective members, Overhaul ceases fighting and will talk to Tomura again after he calms down. Himiko and Twice want to kill Overhaul for murdering Magne, but an equally angry Tomura stops them. As he walks out, Overhaul throws a business card at Tomura's feet and tells Tomura to call him again after he has calmed down and thought about the organization he wants to build.

Quirk and Abilities
Compress (コンプレス): Atsuhiro's Quirk allows him to "compress" anything in a spherical area into a small marble without actually damaging it. If used on a person, it effectively entraps them, terminating the fight instantly and allowing Atsuhiro to abduct them easily.

Enhanced Speed & Reflexes: He is endowed with quick reflexes and impressive acrobatic skills. He is able to dodge Shouto's ice, even when the latter uses his Giant Ice Wall, with little effort, despite being on top of a tree. He is also very fast, quickly distancing himself from the U.A. students by running on the treetops.

Genius-Level Intellect: Atsuhiro considers himself an expert in deception and illusion. True to his words, he was able to restrain Katsuki and Fumikage without their comrades noticing, and he was spotted only when he decided to make his presence known. He also tricked his pursuers into thinking the marbles in his pockets were those of the two boys, while those were actually dummies he had prepared while dodging Todoroki's attack.

Shigaraki Tomura
Atsuhiro appears to have a sense of loyalty to Tomura similar to Kurogiri. His actions and instructions during the battle between All Might and All For One were thought out for Tomura's interest.

After his teammates escaped, Atsuhiro was seen alongside with Tomura while the other members were separated elsewhere.

League of Villains
Atsuhiro seems to genuinely care for his teammates. He does not view his teammates as merely hoodlums who commit acts out of just evil purposes. Rather, he seems to understand their circumstances and can relate to their situations.

During the battle between All Might and All For One, he took charge of the situation for the best interests of his teammates: instructing appropriate actions for Tomura and compressing Dabi in order to carry him to safety.

After the battle, he made sure that the members regularly contacted one another to make sure none of them are caught and puts them in danger.

Quotes

 * (To several U.A. students) "We're just a bit fanatical when it comes to our values. All we wish is to show him that there are other ways. Because you kids today... you have your values chosen for you."