He is recognized by his large build (might partly be contributed by obesity), as well as his mean, selfish and violent behavior. He "rules" the neighborhood with force, often to the physical expense of other children, especially Nobita, who often resorts to asking Doraemon for gadgets to get even on him. In addition, he has a tendency to rob things from other children, usually Suneo, who offers himself to be Gian's sidekick in most occasions.