The Namikaze clan was one of the Ghoul clans. Clans of highly trained monsters with a taste for human flesh. This made them extremely deadly ninjas, as long as they had the disciplinary skills to refrain from eating their comrades, they were perfect ninjas. But, the Namikaze were the most well-known, throughout Ghoul society, and feared by most. Most Ghouls would die for a chance to torment at least one member of this clan.
Of the Namikaze clan's members, Minato was the best known. He was also the fourth hokage of the Leaf Village. It is almost completely unknown that he had a kid with Kushina Uzumaki. That kid being Naruto Uzumaki and making him half ghoul, half human. Under normal circumstances both of Naruto's eyes would be able to transform into that of a ghoul's. But since the Uzumaki's had such strong life force and chakra it pushed against the ghoul DNA and thus gave Naruto only one ghoul eye.
Minato had fucked up, his wife had given birth to Naruto, then someone releases the Nine Tailed Fox that was sealed within Kushina. Minato seals the beast into Naruto, half of it of course, but both Minato and Kushina are killed by the fox. Now sure Naruto's last name of Namikaze would never be released to the public, but damn Naruto looked just like Minato. And people weren't exactly stupid. Well not all of them anyway.
And a large amount of the people that could figure out that Naruto was Minato's son, were in a group, this group being known as Aogiri. This group also happened to hate Minato. And one such member also happened to hate anyone related to Minato just by association. This Ghoul was Yakumo, a large man.
Too bad for Naruto the Hidden Leaf Village literally knew nothing about ghouls. Except that they feared them and Naruto was associated with them. However what happened to Naruto when he was only 8 would change him forever.
One day, when Yakumo was taking a walk through the village, he had spotted Naruto bent over in alleyway. Yakumo could tell he was a ghoul by his scent, except something was very strange about this particular boy's scent. Something about this scent reminded the large ghoul of someone, not sure who, Yakumo walked over for further investigation. Once he arrived he saw that Naruto was throwing up and when he turned around, Yakumo immediately saw the image of the widely despised Minato Namikaze. Being filled with anger he grabbed the boy by his face and hauled him to the building Aogiri provided him.
Yakumo strapped the boy to a chair and began to torture him; taking off his finger and toe nails; ripping off or breaking his fingers, toes, different parts of his fingers and whole limbs, but never anything fatal. It was really quite gorey. Yakumo tortured him for four consecutive years. Making him decide who to kill and making the boy eat whomever he did kill. Finding new and even more horrible ways to hurt him after the blonde regenerated his lost extremities. Just after one year, Naruto had lost count of just how many humans and ghouls he had consumed. Yakumo tried to make the boy count backwards from 9000 subtracting 7, but Naruto quickly lost the number.
When the second year had came about Naruto was completely devoid of all emotions. His brain had gotten rid of them, as a defense mechanism. He ate three ghouls a day now, without any remorse. Good thing that ghouls reproduced at a rate lesser than Humans, so as to not drive their food source into extinction. But Yakumo was also responsible for his lack of emotions, his psychological torture being the reason of course. Yakumo was somewhere between infuriated and pleased that Naruto shut off his emotions. Pleased that he hurt the child so much, but infuriated that Minato's spawn had gotten rid of an entire branch of torture.
About half-way through the second year, Yakumo did something new. He removed Naruto from the chair and instead strapped him onto a table. He completely stopped all torture and just left him there. With ghoul carcasses to eat because he didn't want the boy to die. There was a surveillance system watching the boy, so Yakumo could leave whenever he wanted too. And that the man did, he left and let Naruto stew in the dark, with his broken self. Yakumo just left him there, in the dark, and did nothing to him. He did have a person that was completely masked and disguised drop a carcass on him every now and again. But, other than that, Naruto was completely alone for about 23 hours every single day.
Yakumo was planning to keep that up for six months, seeing what the lack of interaction and confinement would do to him for so long. But after three months, the half-ghoul began to talk to himself. He kept himself company with a second personality. Getting the worst result(in his opinion) possible, Yakumo began thinking about all the different ways to torture someone, Yakumo turned on all of the lights in the room when he was sure the boys eyes were wide open. Seeing the kid's eyes tightly closed brought him mild annoyance. He was hoping that Naruto had been staring into the everlasting darkness.
Yakumo had his cronies set up a little fountain like thing that would drop water onto Naruto's forward at random intervals in the span of a minute. It was set like that so Naruto never knew when the water was going to drop onto him, but he knew it was coming. Yakumo had read somewhere that if you drop a droplet of water onto a man's head for long enough, it would drive him insane.
And after three months it had the exact effect Yakumo wanted. Half-way through that time period Naruto shouted for about two seconds whenever the water hit him. And after only a week of this shouting Naruto lost his voice to the act, but he still flinched. At the end of the aforementioned three months the tortured boy was a blank slate, no reaction to the water what so ever. After a bit of thinking on Yakumo's part he came up with an ingenious plan.
He took Naruto from the table and fountain and put him into an arena type thing. This arena was made out of white extremely hard to break stone. This arena supplied 3 ghouls to fight a day. One ghoul in the morning, one at noon and one in the evening. With only three incentives: Food(The ghouls of course), water for each kill and if he didn't kill them, they would kill him. Whenever he wasn't fighting a ghoul he was just standing there. And for sleep he just flopped backwards.
Each ghoul was completely different in every way possible. Some wanted to kill him, some wanted to eat him, some were girls and wanted to procreate with him, some didn't want to fight at all, but regardless of what they wanted, Naruto killed and ate them. However the boy never ate a human. Not once, he killed them when he had to, but he never ate them. Yakumo speculated that it was a combination of only eating ghouls, being half human and inheriting his father's self-control and will. His father must have had some amazing self-control not to eat his wife, especially when they created Naruto. However, after two years of killing and eating ghouls, Naruto was thrown back into the outside world. Yakumo had gotten every single possible kick out of torturing him. Luckily for the boy his skin was naturally tan so he wasn't as pale as a vampire. But now the kid was twelve and completely ignorant on how to function by himself.
Not knowing what to do, Naruto wandered around until some random guy picked him up with white hair and a mask and took him to the Hokage's office. Once at the hokage's office the guy with a weird mask and gravity defying white hair, displayed the boy to the Third Hokage.
"Naruto! Good job, Kakashi. You may leave now." Hiruzen congratulated and dismissed the man who found Naruto. However the man didn't leave, but he instead said something. Kakashi knew that nobody would take Naruto in or accept him. So he wanted to propose something to the Third Hokage…
"I propose that we publicly execute him."