The World You Showed Me by kashaminami
“A world of bloodshed and death - that was the world I was brought into, it was the only world I knew.
I want to a world without pain, without sadness, a world where I wouldn't be punished for smiling. I want to be a part of the world you showed me.
:Nagisa was one of the youngest and deadliest killers in history. But he wanted to change. And the only way to do that - the only way he can escape - is by taking up a new identity: a new name, a new face, a new life. Sure, he might have to wear skirts and dresses from now on, but it was the only way he could think of to keep himself from getting caught and being brought back to his old life.
And it worked, for the first two years. He joined a normal school, in a peaceful country and he even made a few normal junior high school friends.
Then, he was put into Class 3-E.”