The Demonata series by Darren Shan
Grubbs Grady has stiff red hair and is a little big for his age, which means he can get into R-rated movies. He hates history and loves bacon, rats, and playing tricks on his squeamish older sister. When he opts out of a family weekend trip, he never guesses that he is about to take a terrifying journey into darkness. Hungry demons and howling werewolves haunt his waking nightmares... and threaten his life.