History#
Tenko Shimura was the youngest son of Nao and Kotaro Shimura, and had an older sister named Hana. He lived in a house built by his father for the whole family, including his maternal grandparents Chizuo and Mako Magi.
When he was born, All For One came into his life and stole his original Quirk Factor that he inherited from his parents, making him Quirkless. Tenko's birth itself had been orchestrated by All For One, convincing Kotaro to have another child, all with the end goal of turning Tenko into his own vessel with a warped willpower capable of stealing One For All.
Growing up, Tenko was fascinated with Heroes, but Kotaro, who hated everything to do with Heroes, did not tolerate his acts and often scolded him. His mother and maternal grandparents were always there for him and comforted him when he was sad, even though they hardly dared to oppose Kotaro. One day, when he was five, Tenko saved his friends from being run over by a truck, and All For One, under the guise of a senile old man, offered to walk him home. As Tenko held his hand, All For One secretly transferred a new Quirk, Decay, onto Tenko.[1]
After being brought home, Kotaro took Tenko outside as punishment. Nao begged her husband to not get violent but Tenko was left outside alone without any food or drink. Kotaro did not allow him to re-enter the house until he apologizes for disobeying his rule. When his wife and parents-in-law asked Kotaro whether he was being too harsh with Tenko, he replied that he must respect his rule and forget about heroes.
Nao noted how his allergies have gotten worse, while Kotaro mentions that he hasn't manifested a Quirk yet, so he's doing this to prevent Tenko from suffering, saying that aspiring to be a hero will only end up causing him pain, suffering, and misery.
The next day, Nao comforted Tenko, who continues to scratch his face, unaware of what was causing his allergies. His mother would like to know the reason that causes these symptoms and Tenko mentions that it only happens when he is at home. His mother then asked him if he wanted to be a hero, Tenko replied yes and that he usually plays heroes with his friends. Tenko asked if his father hates him for wanting to be one. She said no, but his attitude was because he knows how difficult it is to be a hero.
To try to cheer him up, his older sister Hana took Tenko to their father's office and there she showed him an old photo of their father when he was a child with his their paternal grandmother. Hana tells Tenko that their paternal grandmother was a hero, and this revelation made Tenko very happy. Hana tried to support his dream, even saying that she wants to follow his dream herself, encouraging her younger brother that they can be hero siblings one day.
Later on, Tenko was playing with Mon, the family dog, happy to know that there was a hero in his family. While playing, he suddenly felt an unpleasant twinge in his right hand, and unbeknownst to him, a part of the ball he tossed crumbled off. Unfortunately, he had no time to reflect on what had just happened as his father had discovered that his children snuck into his office and saw the picture of his hero mother, Nana.
Kotaro demanded to know who was responsible. Scared, Hana broke down into sobs and blamed it on Tenko, saying it was his idea and he had shown her the picture, instead of what actually happened. Furious, Kotaro took his anger out on Tenko by beating him as the boy's itching got worse. While punishing his son, Kotaro shamed the heroes, claiming that they hurt their families to protect strangers that they don't even know, telling his son that the woman in the picture was not his paternal grandmother, but a monster that threw away her own child. Tenko's suffering was watched by his other relatives, who he begged for help but they could only witness it in horror.
After the beating, Tenko was punished to stay in the backyard. He was crying inconsolably, hugging his dog Mon while he continued anxiously scratching himself. While outside, Tenko confided in the family dog of how he couldn't take anymore of the abuse, and he hated everyone for leaving him to suffer at the hands of his father.[2] As he was clutching his dog, Tenko's Quirk activated for the first time, causing the dog to crumble in his hands into a pile of blood. Seeing this caused Tenko to freak out in fear, trying to understand what had happened, initially thinking he and the property were under attack by a villain and didn't realize it was his own doing.
Afterward, Hana came outside to apologize to Tenko for having framed him. Tenko tried to warn his sister of the danger, but the shock he suffered prevented him from speaking. Hana noticed something was wrong with Tenko and approached him, but screamed in horror upon seeing their dog's remains and ran away. Tenko tried asking for her help, scared of what would happen if Hana told the family about the dog, but as soon his hands touched Hana, he ended up disintegrating her by accident. Seeing his sister die in front of him further traumatizes Tenko and makes him vomit.
Tenko's maternal grandparents and mother ran outside to see what was happening, being horrified by what they saw. Thinking about how they never did anything to protect him from his father, Tenko feels only bitter hatred for them, causing him to decay the ground beneath him and destroying the entire backyard. Despite his feelings, Tenko still begged them for help. As she started to crumble away, Nao tried to reach out to her son and comfort him, but her body fell apart before she could. Tenko's maternal grandparents also ended up dying in the process.
Kotaro was alerted by the noise and discovered the destruction. Standing horrified, Kotaro could only stare at the scene while Tenko begged him for help and the area around them was destroyed. Tenko ran to him for help but his scared father grabbed a pair of pruning shears, which he then used to hit his son across the face before yelling at him to stop. This time, an enraged Tenko charged at his father with full intent to kill him and touched his face; ultimately the spreading decay ended up destroying the entire house. Tenko would relish in ending his father's abuse.[3]
After the deaths of his family, an orphaned Tenko was left to fend for himself on the streets. Tenko wandered around the city dazed and confused, mentally pleading for someone to help him. People who passed by took one look and pretended not to notice him, unnerved by his scary appearance. The only one who tried was an elderly lady, but Tenko's appearance was disturbing enough to scare her away, saying that a policeman or a hero would surely arrive to help him.
Tenko began to think that no one would help him as punishment for killing his family, as the memories slowly faded into the recesses of his mind.[4] Eventually, All For One came looking Tenko, homeless and alone under a bridge, telling him it must have hurt that no one came to help him, despite his hopes to be saved. All For One embraced a crying Tenko while blaming society for the reason he was not saved sooner. He took Tenko home, declaring that from now on, he would be his master, using this incident as a means of stimulating Tenko's newfound bitter hatred for heroes and began grooming him as his adoptive son.
Tenko was given his own room by All For One, and Kyudai Garaki "gifted" the young boy with the disembodied hands of his deceased family members. This causes Tenko to receive a violent shock to his emotional state, seeing fragmented glimpses of old memories of his family, before vomiting. Kyudai asks if All For One will modify Tenko, but All For One decides not, so that the feelings of hatred will linger within Tenko, as he will teach him how to give them purpose.
Enduring the sensation the hands caused to him, Tenko embraces his family remains.[5] All For One told him that he had an impulse to destroy that couldn't be controlled, and when he doesn't satisfy those urges, that's when he feels that unpleasant itchiness in his body. He assured him that the impulse didn't have to be controlled, nor was it necessarily a bad thing.
Later, Tenko had a fight with two thugs, who beat him up. Tenko wants to kill them with his Quirk but backed down, much to his shame, and leaves the place. Once in his room, Tenko began to scratch violently because of the itching that he feels. All For One tells him that concepts such as conscience, morals, and ethics were just things that people use to manipulate the world to how they see fit and encouraged Tenko to do whatever he feels like to make himself feel better, otherwise he would suffer for it.
He asked Tenko what he wants to do in those moments. While staring at the hands of his family, Tenko replied he wants to murder the two guys who beat him. He explained that he couldn't hold back his feelings anymore, grabbing one of the hands and disintegrating it with his Decay. Satisfied with his protégé's response, All For One told him that he already knows what to do.
Tenko returned to the place where he confronted the thugs, only now wearing his family's hands attached on him, following the advice of his mentor to take his family always with him. The punks called him creepy, asking what he wanted with them, but Tenko only crumbled them with his Quirk, leaving a pool of blood and pieces of the bodies of the thugs. He thought about how sick and disgusted he felt, but also noted, with some confusion, that he felt completely calm, and felt like he was allowed to do anything he wanted.
On a nearby rooftop, All For One and Kyudai watched the entire event. The doctor said that he thought Tenko had forgotten his memories, but All For One corrects him that they have always been there, just shut away. He noted that his family's hands would serve to restrain him, keeping all but his negative emotions suppressed. He saw that Tenko is subconsciously keeping his Quirk in check. Smiling, All For One expressed pride in seeing Tenko's first step down the path to becoming the Symbol of Fear.
Back home, All For One congratulates his disciple for what he has done and rewards him with five new hands so that he will always remember that day. Four of the hands belong to the punks he killed, and when Tenko asks him about the fifth one, he explains it's a small bonus to make up for the one he destroyed earlier.
Once Tenko put on all the new hands, All For One said he was reborn as Tomura Shigaraki. Tenko was confused by the name. All For One explained that "Tomura" came from the word "Tomurau" which means "to mourn", as it signifies the sadness that comes with death and parting. And "Shigaraki" is All For One's real last name.[4]
After this, All For One began to educate and raise him as part of the League of Villains, to eventually become his successor of the organization. At one point, All For One and Kyudai's Nomu, Kurogiri, was tasked with aiding and overseeing the development of Tomura Shigaraki.[6] Tomura also at some point witnessed Kyudai taking part in an experiment with a man known as Nine.[7]