Rock Ness Monster is the character from the Storybook Segment: "The 3 Wee Lasses and the Rock Mess Lobster" of the episode: We Totally Rock! He guards the bridge Molly, Oona, and Deema need to cross in order to attend the rock and roll festival. However, only those who "totally rock" can cross. And those who do not might get eaten. In the end, the girls end up taking the excited lobster to the festival.