The boy who could see demons

I first met my demon the morning that Mum said Dad had gone.

'My name is Alex. I'm ten years old. I like onions on toast and I can balance on the back legs of my chair for fourteen minutes. I can also see demons. My best friend is one. He likes Mozart, table tennis and bread and butter pudding. My mum is sick. Ruen says he can help her. Only Ruen wants me to do something really bad. He wants me to kill someone.'