Corey, Laney, Kin and Kon against the green screen in their mocap suits. (Screen grab from GBS01E05 'No Strings Attached')
Sigh. If it were only this easy.
GROJBAND is actually animated in FLASH. The main character models are drawn from a number of angles with multiple hand positions, eye-blinks, and full mouth charts. These pieces are considered MDP (Master Design Pack) and the animation crew skillfully moves them around to make the actions that you see in the show. For the most part, the master designs cover all the the actions that the characters need to do. Sometimes though, the characters need to be in a position, or make an expression that the animator just can't recreate. For this, our posing department creates scene-specific drawings. Above is a sample of the custom posing done for 'No Strings attached'.