Tomura Shigaraki, born Tenko Shimura, endured severe childhood neglect and abuse from his father, Kotaro Shimura. Kotaro despised heroes, forbidding all admiration and specifically targeting Tenko's interest, enforcing this with physical punishment and isolation. Tenko's paternal grandmother was Nana Shimura, a Pro Hero and mentor to All Might; Kotaro resented her for prioritizing heroism over family. Tenko's Quirk, Decay, manifested during intense emotional distress. Unaware of his power, he accidentally disintegrated the family dog, then his sister Hana when reaching for help. Overwhelmed by trauma, he subsequently killed his mother, maternal grandparents, and finally his father, who attacked him instead of offering aid. After these events, Tenko wandered the streets alone; bystanders avoided him, and no heroes intervened, deepening his resentment toward society. All For One found him, manipulated his trauma by blaming hero society for his suffering, and took him in as a successor. All For One had engineered Tenko's birth to be Quirkless and later implanted the Decay Quirk, intending to mold him into a vessel. Tenko was given embalmed hands of his deceased family as psychological restraints, suppressing positive memories while fueling hatred. Reborn as "Tomura Shigaraki"—a name derived from "tomurau" (to mourn) and All For One's surname—he was groomed to inherit All For One's legacy and destroy hero society. Tomura's early villain persona exhibited instability and childishness. He led the League of Villains with erratic, tantrum-like behavior, frequently using video game terminology like "cheats" or "game over" to describe real events. His appearance featured fourteen disembodied hands attached to his body, including his father's hand worn as a face mask; he referred to this as "Father" and relied on it emotionally. His primary goal was killing All Might, the Symbol of Peace, viewing heroes as hypocritical enforcers of a flawed society. Despite his volatility, Tomura demonstrated keen tactical intelligence, quickly analyzing opponents' Quirks and adapting strategies mid-battle. His leadership evolved over time; he developed genuine loyalty toward League members like Himiko Toga, Twice, and Spinner, treating them as comrades rather than pawns. He avenged them when harmed, notably confronting Overhaul for maiming Mr. Compress and killing Magne. After merging the League with the Meta Liberation Army to form the Paranormal Liberation Front, Tomura became its Grand Commander, gaining resources and influence. Tomura underwent transformative power augmentation when implanted with the original All For One Quirk. This procedure caused physical changes: his hair turned white, his physique became more muscular, and he developed holes in his palms. The process allowed All For One's vestige to temporarily seize control of his body. Tomura resisted this possession, reclaiming autonomy and declaring himself the "Symbol of Fear." His Decay Quirk amplified significantly, enabling disintegration of entire cityscapes without direct touch. Combined with stolen Quirks like Super Regeneration, Search, and Air Cannon, he achieved near-invincibility. However, overusing these powers in an incomplete body caused progressive physical decay, marked by cracks and scars. During battles against Pro Heroes and Izuku Midoriya, Tomura's motivations crystallized beyond mere destruction; he exposed societal failures, citing his own abandonment as evidence of heroes' selective compassion. He rejected All For One's control entirely, vowing to destroy everything connected to his traumatic past—including the existing world order—to find personal salvation. Tomura's relationships defined key aspects of his arc. All For One acted as a manipulative mentor and father figure, exploiting Tomura's trauma to serve his own goal of body usurpation. Despite initial reverence, Tomura ultimately fought and overcame his master's influence. The League of Villains became a surrogate family; he supported their autonomy and shared their goal of societal upheaval, contrasting All For One's transactional cruelty. His rivalry with Izuku Midoriya centered on their opposing paths: both were once Quirkless outcasts, but Tomura embraced destruction while Izuku upheld heroism. Their final conflict involved a metaphysical battle within the Quirk vestige realm, where Izuku and Nana Shimura reached out to Tomura's suppressed humanity. In the climax, All For One reasserted control over Tomura's deteriorating body during the battle, leading to catastrophic Quirk overuse. Though Tomura's body disintegrated, his soul was spared through Izuku and Nana's intervention, allowing him a moment of acceptance before death.