Jeffy can be described as a mentally handicapped teenager, who usually makes an odd “OUH” sound whenever he’s happy, mad, or feeling some strong emotion. Or, he can do it randomly for no reason. His adoptive father is Mario (yes, Super Mario) and adoptive mother is Rosalina. His friends are Junior, Joseph, and Cody. He usually calls his father, Mario, “Daddy”, as he acts like a child at some times. If Mario gives him green beans, he usually throws the plate on the ground. He is a puppet.