Slim is a cinnamon brown stick insect and a clown in P.T. Flea's circus troupe. It appears that he is unhappy with his position at the circus troupe, as his boss constantly casts him as a prop instead of a character, with such castings as a broom, a pole, a stick and a splinter. He is shown to be best friends with Heimlich and Francis, and often treats other bugs with more respect in contrast to Francis' aggressive nature. However, he seems to tolerate it, as seen when he calmly broke up a fight between Francis and a couple of flies during a performance. Unlike most stick insects, Slim does not have wings and cannot fly. Because of this, Francis usually carries him for transport.