In the life of Koji, he was the second born between him and his sister, Asami. The entire family resided on the outskirts to Kirigakure. His sister was born three years prior to him, and their parents Daiki Hiroki and Daiki Chika. Within the first few years of Koji's birth, he had most of their parent's attention, and Asami had started getting envious, of him, though she still loved her younger brother. Asami was always a tough girl though she never looked it. She had dreamed of becoming a high ranked shinobi. As soon as Asami entered the Ninja Academy, Koji was inspired to follow in his sister's shadow, to try and become as strong as she was.. Koji was happy throughout his childhood but had few friends. He mainly spent time with his parents and sister, and occasionally they had someone over, Koji would be the shy child towards them, while Asami was the one who would ask them questions, and be talkative. But if someone had ever harmed, or even spoke bad about his sister, even if she wasn't there, Koji would get mad and do what he could to stop them, but he usually the one to get beat up. Usually after the third time getting knocked down, Asami would show up just as Koji was starting to tear up. Though as soon as he saw her, he did his best to hold back his tears, but she always thought that he was trying to be strong for her, which he was to the best of his abilities.
Soon after Asami became a Genin, and a while before Koji entered the Academy, at night after dinner when Koji, Asami and their parents were spending time with each other, a group of bandits attacked their house. Even though Asami's and Koji's Father had been a Shinobi before, he wasn't a match for the leader of the bandits and was killed off quickly, but only after they had their fun torturing him. Asami did her best to try and stop the bandits, which caught them off guard, so she was able to seriously injured one with a small weapon, but was quickly knocked out and tied up soon after her surprise attack. Koji was tied up as well, but didn't have enough knowledge or anything to try to help. This is one of the only times that he actually let his emotions take over him while near his sister, letting his 'tough kid' act down. As soon as the bandits finished torturing and killing Hiroki, the bandits soon moved over to their mother. There were a total of six bandits, each strong, but also ruthless. When the bandits moved to Koji's and Asami's mother, they had the plan to have their way with her while both Koji and Asami were still in the room.
After a while, after the bandits were done having their way with Chika, the bandit leader killed her with a slow and gruesome death. He cut open her chest carefully, reached his hand between two ribs, and grabbed her heart. By this time she was going in and out of consciousness while the bandit leader was doing that. But during the time she was conscious, she was yelling in pain. Asami was still out cold while this was happening, but Koji was wide awake and was crying. Soon, the bandit leader squeezed her heart, thus killing her almost instantly. When Chika died, she was looking at Koji and Asami, with tears rolling down her face. That image was quickly burned into Koji's mind. After the bandit leader took his hand out of Chika's chest cavity, the leader walked over to Asami, who was just waking up. He picked her up, and and started to walk out with her. Koji yelled at them to stop, while he was crying, but all one bandit did was knock him out, because it seemed he didn't feel like killing or witnessing another kill in the same house.
A few hours later, Koji woke up, still tied up. He moved slowly over to the knife that was on the floor when Asami tried to kill one of the bandits. He cut through the rope that was used to tie him up. He smelt the bad odor of iron, due to the blood that was all around the house. He stumbled out of the house, still sobbing a little, and seeing his parents dead bodies again. As soon as he reached grass, his body felt heavy and he fell to his hands and knees. Soon after he fell to his hands and knees, he felt sick at the sight of his parents corpses and vomited.
About two years after his parents were killed, and his sister was kidnapped, he entered the Academy, determined to get the people that had killed his parents and kidnapped his sister, though not knowing if they were still alive or not.
After entering the Academy, he studied his hardest, even going through several classes and even getting tutored by people until he quickly graduated and became a Genin. It wasn't long after he had become a Genin that he had soon started to feel some pain in his palms at least once a day until a few weeks passed of him doing some missions and some training before the pain became unbearable for a few hours and he soon noticed some slurping coming from his hands and some longs going across his palms. It wasn't long before they opened up, revealing to him, to be mouths. He went on his way the next few days, still freaked out until he tried to go and write a letter at his home and the mouth on one of his palms tried to chew the paper, grabbing a bit before spitting it out in disappointment. Koji looked at the paper for a bit before trying out different materials the next few days until finding out clay was what they chewed on and even learning that they were infusing chakra into what they were chewing, which caused him a little bit of trouble as he didn't know what it was going to do as some of the clay had detonated in public.
Time passed, and Koji learned more and more, practicing, and even getting better with this new ability of his, he would become a Chuunin with focusing on more of his missions. Upon going into one of his more difficult missions and losing a squad mate, he'd get more into his training and learning more, time passing. It was months of training with missions here and there and he would eventually run into an unforeseen enemy, which would brand him with some sort of seal before running off, no matter how hard he tried to stop the man. He would slowly return back, in pain due to the seal. He would go to a library outside of mist to see if he could research what was given to him, and apparently it was something called a Cursed Seal. On his way back to Kirigakure, the Curse Seal he had received started to cause him more and more pain, and it wasn't until he reached his home did it eventually become unbearable. Luckily, he was at a point in time that he wasn't with someone who had left him soon after getting with him and betraying his emotions. The pain did, however, become physically unbearable for him that he couldn't move much and even became too much for him that it caused him to pass out.
As he regained consciousness, he could quickly tell that there was some liquid soaked on his clothes, and looking around, he could tell he was laying in a puddle of... well he couldn't initially tell by sight as it was dark out comparatively to what he thought, but a moment passed and he could tell what it was without even confirming it with his sight. Blood soaked his clothes and his body continued to hurt, but at a decently tolerable level. He would move and turn on a light, and seeing the blood soaked clothes he wore, as well as several scratches and some runic marks on his body that quickly disappeared. Confused, dazed, and still in pain, he would move to his bathroom, grab a towel, and take a shower to wash off the blood after stripping off his blood soaked clothes.
After he finished his shower and redressed himself after bandaging up some of the scratched he had on him, he would go and try to get blood out of the mats on the floor where he was laying for however long he had been there. Doing so quickly, he heard knocking and shouting at his door, in which he would rush there and open it, but find nobody there and the sounds stopped the moment he had opened the door. Thinking it was done, he'd go and actually sleep rather than some restless time after having passed out.
Time passed after that day, up to over a year, allowing him to do enough missions to become a Jounin, he would be content for the time being, going out on another mission soon after ranking up. The mission was normal until Koji saw the man that had initially gave him the Curse Seal, and had blacked out for, yet again, an unknown amount of time. When he came to, he was covered in blood and the squad mates he was with were dead, as if they had just exploded into red mist. He soon heard laughing, as he looked around, but as he noticed no one was around, he noticed that he was him laughing. Shaking his head and regaining his composure, not noticing the curse seal on him spreading runic symbols across his skin. Returning back and finishing the mission, he'd take some time, enough to feel better, going on a few missions, with each mission having him black out at some point, occasionally before he dealt with anyone around him. The white haired man would finish up a job that he had blacked out throughout most of it, feeling extremely drained at the end, the Cursed Seal draining his body as he had the seal.
Upon returning to Kirigakure from this mission, Koji found the village completely frozen over, even the water just outside of the village was frozen. Well, it looked like it was time he could finally go and search for any information freely on what could be going, but every time he did so, he'd black out. Every time except for the final time, which he was able to force himself to keep himself all there by some physical pain. Every needing to cause himself enough pain that he could stay there, he would learn more about the Cursed Seals, finding out there was more than he thought, and even finding out that they could take over someone in a sense, virtually corrupting them for power. And after a quick black out after finding the passage within the book, he would find himself outside of the building, not wanting to see what damage was done inside before leaving to find more things out.
