He is a scoop of yellow ice cream resting in a water cone cup. His face, arms and legs are nearly identical to that of SpongeBob's. He also has chocolate chips where SpongeBob's pores would be.
He introduced himself to SpongeBob and Patrick, and then introduced them to his best friend Popsic and the rest of the main ice-cream themed characters. SpongeBob and Patrick then became hungry, and CreamBob offered them ice cream cakes and ice cream sandwiches, before telling them to check the ice cream truck.
After SpongeBob and Patrick devoured the ice cream truck, CreamBob suggested about going to play in the Goober Lagoon, as best friends, though SpongeBob and Patrick decided to eat him, his friends, and the entirety of Pint Bottom.