Scammed

Demon did not know anything about his childhood or where he came from. He was the one who was trafficked as the youngest among the other children he grew up with as slaves for that organisation. 

It was also the reason he was raised to be the assassin. 

The other children had some awareness when they were kidnapped and enslaved. Therefore, most had already developed human feelings and a sense of morality. It was difficult to crush their humanity enough. 

But Demon was just a baby. 

He was moulded into a killing machine even before he could walk. His body and mind were put into a pressure cooker of the worst situations a child could be in, and it made him a great killer. 

After watching the other kids, Demon realised he was different from them. They seemed to have something he did not have: an element of humanity. He knew he could never be like them.

They were just different people.