The smell of melted tin and grease pervaded the dense air of the underground workshop, a concrete sanctuary and exposed wiring hidden underground in the outskirts. Under the cold, oscillating light of tubular lamps, the boy observed his own long, calloused fingers. In its palm, small cubes of neon blue light - gleaming digital voxels - floated in perfect harmony before dematerializing, compressing a device into its internal data core. For those who saw him from the outside, he was just an incredibly tall fifteen-year-old, 1.84 m tall, broad shoulders and an inverted triangle athletic posture. But inside, the mind of Lim Ryung Gu - named by the city's shadows as Ren Sato - functioned as a perpetual supercomputer overheating.
The silence of the place was interrupted only by the discreet hum of its own biology. The Digital Dynamo, his Individuality, had awakened when he was a mere four years old. Ryung Gu's earliest memories were not of toys, but of the heat of soldering iron and the smell of copper in the hands of his father, a brilliant electrician in Busan. At the age of five and six, while other children were playing, he was already helping to repair complex motherboards, fascinated by the invisible flow of electrons. This nostalgia, however, was always accompanied by a bitter snare of frustration. Industrial automation has swallowed up the family's livelihood, pushing them into forced immigration to Japan and, finally, into the misery of a slum falling apart.
Ren's deepest pain came not from poverty, but from the disdain of society. He could still remember the staggering crack of the concrete when the building collapsed. Outside, the skies of Tokyo trembled under the confrontation of giants: All Might and All For One duel without shame for collateral damage. For the heroes at the top, that tenement was just a blur in the landscape; for Ryung Gu, it was the grave of his parents, who gave their lives to get him out of the wreckage. Covered in dust, blood and crying, the eight-year-old learned the most valuable lesson of his life: heroes do not exist to save those who live on the wrong side of the tracks.
It was in the garbage and in the rain of the streets that the Tsuchigumo Union found him. The memory of his first encounter with Kenjiro Arata still made Ren's spine shiver discreetly. The leader of the gang was a living monstrosity: an imposing man surrounded by three pairs of arms and two lower limbs - eight legs in perfect synchrony - with four pairs of eyes hidden by sunglasses and jaws that opened to reveal poisonous chelicerae. Kenjiro saw in the child prodigy not a traumatized child, but a crude tool to pay off the debts left by his parents. There, Lim Ryung Gu was pronounced dead on paper, and Ren Sato was born as a union property.
Ren's childhood was torn between farce and brutality. In the morning, he attended public school as a silent and untouchable student; in the afternoon and evening, he underwent exhaustive training in taekwondo, kickboxing, parkour and street fight, learning to use the agility of his long legs and the explosive force of his torso to transform into a lethal weapon. But the real watershed occurred at the age of eleven, when Kenjiro delivered it into the hands of The Doctor.
The surgeries were a nightmare of cut flesh and molten metal. In order for his body to withstand the apex of the Digital Dynamo, Ren was reconstructed: his musculature and bones were coated with light metal alloys, his eyeballs were replaced by multispectral optic-technological prostheses under cranial plates, and his cerebral cortex was accelerated to a genial level. The physical pain of the interventions eventually passed, but the mental sequelae remained. His brain's processing capacity increased so much that his thoughts rotated at a thousand per hour, generating an incessant stream of data, ballistic calculations and smudged noises that often suffocated him.
In the workshop, however, Ren found his only moment of peace and control. He loved the creative process. It was fascinating to take pieces of scrap stolen from car depots and turn them into the Driving Blaster, gravitational mines or optical camouflage and quantum translocation systems. When he stocked these prototypes in his "Digital Inventory," converting matter into blue voxels, he felt he had absolute dominion over his micro-universe.
The routine in the Tsuchigumo Union, however, demanded its price. At the age of thirteen, already as Kenjiro's right-hand man, Ren carried out dark missions of espionage, digital intrusions and the erasure of entire identities. Mental exhaustion and accumulated trauma led him to seek refuge in the chaos of clandestine parties. Leaning on the corner of sofas in noisy nightclubs, under the pretext of negotiating arms and drugs for the union, Ren smoked cigarettes or marijuana and drank until dawn. Alcohol and substances were his only outlet for "turning off" the overactive processor from his head and feeling, for a few hours, what it would be like to be just an ordinary teenager. Behind the mask or motorcycle helmet he wore on the missions, and under the cynicism and acidic humor he adopted as a social shield, a deeply lonely boy was hiding.
His greatest frustration came with Kenjiro's latest coup. At the end of elementary school, when Ren finally envisioned a way to pay off his debts, track the filth behind his parents' death, and perhaps one day return to his native Busan, the leader incarcerated him in a new order: infiltrating the prestigious U.A. as an insider spy for the syndicate.
Determined to circumvent the system, Ren attempted to hack into U.A. servers through cyberspace to forge his enrollment without having to interact with the world of heroes. It was then that he found a worthy opponent. Director Nezu not only intercepted his invasion with annoying ease, but tracked the signal and personally offered him a spot in the institution, fascinated by the chance to test such an extraordinary intellect.