Atsuhiro Sako, better known by his alias Mr. Compress, is a significantly intelligent and theatrical villain from My Hero Academia. His background is rooted in a notable lineage: he is the great-great-grandson of Oji Harima, the Peerless Thief, a figure from the early days of the Hero System who targeted corrupt heroes. This heritage frames Mr. Compress’s view of villainy as a form of showmanship and righteous thievery. He is a member of the League of Villains, initially serving as part of the Vanguard Action Squad and later becoming one of the nine lieutenants of the Paranormal Liberation Front. In the League, he often acts as a voice of reason and a strategic mind, frequently keeping the more volatile members in check and serving as a mentor figure to younger villains. His personality is elegant, charismatic, and calculating, with a flair for dramatic performances and stage magic that he uses to both entertain his allies and disorient his opponents. He is fiercely loyal to his comrades, viewing the League almost as a family, and is willing to go to great lengths, including self-sacrifice, for their survival. His motivations are not rooted in personal trauma like many of his peers but rather in a philosophical commitment to exposing society’s flaws through his actions. Mr. Compress plays a key role in major story arcs, most notably during the attack on the U.A. High School training camp where he successfully captures Katsuki Bakugo. He also participates in the raid on the Shie Hassaikai, where he loses his left arm to Overhaul but retaliates by using his Quirk to tear off one of Overhaul’s arms in return. This injury limits his Quirk use to his remaining right arm, as his Quirk factor is located in his arms. His development shows him adapting to this limitation through resourcefulness, relying more on his stage magic and trickery to compensate. His notable ability, the Compress Quirk, is an Emitter-type power that allows him to shrink any object or person within a spherical area into a small, marble-like object without causing physical damage. The target’s weight is also reduced, making them easy to transport. He can compress parts of his own body for stealth infiltration, and he can release the compressed targets by snapping his fingers. The Quirk is highly versatile for kidnapping, immobilization, and precise maiming, but requires direct hand contact and has a limited range of effect. Despite his physical setback, Mr. Compress remains a cunning and dangerous operative, using misdirection and decoy marbles to protect his captured targets and continue his role as a key strategist within the villain organization.