Roco the dog is Manolo's pet dog and driver of the roco truck. While his master is usally asleep, he drives the truck and watches over the chicken coop. When the trio (Popy, Harchi, and Buck) are on his tail for food, he is sure to make them wish they never attempted to steal from him. Roco will defend his cargo from anybody including Oscar. Roco himself has been seen as a bit of bully and taking pleasure in the other characters misfortune when they fail in their attempts. Roco drives the truck using a pulley system he developed, it's unknown how the truck brakes or goes since Manolo is asleep.
Roco is tough but unused to the desert life as shown when he is forced to traverse without his truck or when chasing Oscar or the trio.