Incubus (Puffin Teenage Books S.) - Tapa blanda

Voices in my head. It's driving me mad. I'll have their tongues. That'll shut them up.
Danny's father has been found guilty of a multiple murder - and Danny is terrified that he will turn out like his father. But was his father truly bad or a victim of something even darker? Danny gradually discovers that his family is being haunted by an evil little spirit: an incubus. And now it's haunting Danny. It broke his father, so what chance does Danny have? He has to be very strong and very careful.