Yuuto's character sheet and backstory!
Yuuto lived in a Christian household from the day he was born to being sent to the Second-to-Last Defense Academy. Surrounded by 5 other siblings, Yuuto was a middle child; twin elder brothers, one younger sister, and the youngest brother. They were all homeschooled, beginning at 6 years old. They rarely went outdoors. The only time they did was when playing in the closed off backyard. Their parents would be home all day every day, teaching their children about The Bible and the dangers of the world. Occasionally they would learn basic math and Japanese, but their parents didn’t believe in science, and therefore never taught their kids about it. They weren’t allowed electronics or many toys, so they often had fun by playing with each other. Yuuto’s elder brothers tended to play too rough with him, so he often decided to play with his younger siblings instead.
One day during recess, his eldest brother, Yuma, suddenly went missing. Their parents panicked and began locking everyone inside. No longer were they allowed to leave the building, and the children’s mental health began to suffer; not only from losing their brother, but being locked up inside all day. Their parents didn't believe in mental health, so when their children began venting their feelings, they were often shut down; especially Yuuto and Yuma’s twin brother Yuuki.
About a month passed. After being called to dinner, Yuuki didn't come downstairs. Yuuto’s mother ordered him to fetch his brother. When Yuuto knocked on the door of Yuuki and Yuma’s past shared room, Yuuki didn’t answer. This prompted Yuuto to enter the room to get to him, but all he found was the corpse of his older brother by the dresser.
Traumatized by both of his older brothers’ disappearances, Yuuto became closed off to the rest of his family. Both of his younger siblings never found out what happened, and they thought Yuuki ran off to find Yuma. Yuuto believed himself to be at fault for what happened to Yuuki, as he never thought to check up on him or talk about it with him.
One day, his youngest brother, Yuuji, fell extremely ill. Yuuto knew what was going to happen; too many of his siblings were gone. He consistently expressed concern to his parents along with his sister Youko. They didn't listen. They believed that if Yuuji was meant to die by God, then he would. They never spoke to a doctor. Yuuto and Youko spent a lot of time by their brother’s bed, telling him stories, feeding him, and observing him. Youko, interested in the medical field, began becoming increasingly paranoid of what could possibly be ailing him. She mentioned seeing a strange lump under the boy’s arm, and suspected he might have cancer. Once again, the two begged their parents to do something, only to be met with inaction. Yuuji died after 3 months.
Youko barely left her room anymore, only to eat and for schooling. Yuuto spent a lot of time in his imagination, no longer able to focus on anything but the world in his head where his siblings were all alive and well. Their parents tried desperately to force them to play together, to interact with them, literally anything but staring off into space. They concluded that they both had been afflicted by the Devil, and planned to send them off to a Christian boarding school to be exorcised. The day they were to be sent off, invaders attacked the Tokyo Residential Complex. They had broken into the house and killed both Yuuto’s parents. He dragged his sister out of her room to show her the chaos, and they both escaped into the outside world for the first time. Trying to escape the carnage, Youko was attacked by an invader and injured badly. She laid in an abandoned building while Yuuto went searching for materials to help her. While searching, he met Sirei, who explained that Yuuto had been picked to defend humanity from invaders.
Yuuto quickly shut him down and rushed back to his sister, to find her surrounded by invaders. His heart racing, Sirei showed up again, offering an infuser so he could fight to save his sister. Yuuto agreed in a heartbeat, quickly shoving the blade into his heart and transforming. He decided to act first and ask questions later. A large hammer created by hemoanima formed in his hands, and he began smashing the invaders to pieces. The closest ones to his sister first, then the ones farther away. After he killed all of them, he tried to rush to Youko’s side, only to be snatched by Sirei and transported away to the Second-to-Last Defense Academy.
Here's his siblings, btw!!