Atsuhiro Sako, alias Mr. Compress, operates as a theatrical villain within the League of Villains and its evolved form, the Paranormal Liberation Front. Descended from the legendary Peerless Thief Oji Harima, he upholds his ancestor’s crusade against societal corruption, specifically targeting affluent heroes and systemic flaws in hero culture. His background as a professional entertainer informs his flamboyant criminal persona, merging showmanship with strategic intellect. Visually evocative of a stage magician, Mr. Compress sports a top hat, mask, balaclava, and a prosthetic left arm—lost during a clash with Overhaul. His attire blends a dark orange shirt, green-striped bolo tie, and knee-high boots. During the Paranormal Liberation War, he endured permanent maiming after employing his Quirk on his lower back to escape confinement. Charismatic and cunning, he balances humor and arrogance with tactical pragmatism, often taunting foes mid-combat. Despite his flair for drama, he acts as a stabilizing mentor within the League, displaying fierce loyalty to allies. This devotion drove him to avenge Magne’s death by attacking Overhaul, sacrificing his arm initially before later crippling Overhaul in retaliation. His Quirk, Compress, grants him the ability to shrink objects or living beings into marbles via hand contact, suspending their abilities and mobility. This power fuels creative tactics: compressing adversaries’ limbs to incapacitate, tunneling through terrain, or launching stored marbles as weapons. Notable exploits include capturing Katsuki Bakugo and Fumikage Tokoyami during the Forest Training Camp Arc by concealing marbles in his mouth and deploying decoys. Strategically vital, he aided in defeating Pro Hero Snatch during the Shie Hassaikai Arc and prioritized liberating allies like Tomura Shigaraki during the Paranormal Liberation War, despite severe physical strain. Post-Final War, his arrest alongside Spinner marked them as the last original League members. His actions consistently undermine hero society, driven by ancestral legacy, ideological defiance of systemic injustice, and unyielding camaraderie.