Ever played fetch with a four-eyed Grerk or made pancakes with a giant orange squurm? Nelly isn't scared of monsters. In fact she babysits for them. Every night, Nelly the monster sitter looks after a new friend, but its never easy...

Slop, the five and a bite year old Squurm, has innumerable Spaghetti-like feelers, two brains and six eyes. He's a practical joker, hates loosing and gets bored very, very easily. Nelly has got her work cut out!