Poesy the Monster Slayer by Cory Doctorow
A monster slayer needs no bedtime! Once her parents are off to bed, Poesy excitedly awaits the monsters that creep into her room. With the knowledge she's gained from her trusty Monster Book, and a few of her favourite toys, Poesy easily fends off a werewolf, vampire, and much more. But not even Poesy's bubblegum perfume can defeat her sleep-deprived zombie parents!