A Monkey Bear is a mythical creature dreamed up by frustrated parents who have kids that don't pay attention or listen. They sometimes have to resort to outlandish stories in order to traumatize their children into paying attention. A child behaving now is better than paying for a psychiatrist later on in life. A Monkey Bear usually lives in a child's pajama drawer and comes out at night and scratches a child's ass regardless of age. In Belize it is also known as El Rascador de Culo or "Ass Scratcher".
Sweetie you need to listen, it's time to go to bed. If you don't go to bed the Monkey Bear that sleeps between your Little Mermaid pajamas and your SpongBob Pajamas will awaken from it's slumber and scratch your little booty.