Charjabug is a small, cuboid Pokémon resembling an insect. Its body consists of three square segments with two brown stubs on each side. The last two sections have a thin, ring-like marking on each side. Each eye is covered by a blue screen and are only visible when they glow. Two short, yellow spikes extend from the front square: one on each side of its rectangular mouth. The mouth itself is gray and has two jaws that close sideways, shaped like a lightning bolt when open.
Natural Abilities It generates and stores electricity in its body by digesting food. This energy is stored in an electric sac. The electricity it stores could run a household for a whole day, and can be shared with other Pokémon. This Pokémon stays immobile as it prepares for its evolution, and is often half-buried in earth or leaves, munching on humus.
Grubbin, along with its evolutionary relatives, were designed by Hitoshi Ariga.
Charjabug appears to be based on a cocooned bug and a battery. It may also be based on the denkimushi, a caterpillar in Japan that, when touched, can give a sting that is said to feel like an electric shock. Based on its cry, it may also be inspired by an accordion.
Charjabug may be a combination of charge (as in to charge a battery) or charger and bug.
Dendimushi may be a combination of 電池 denchi (battery) and 地虫 jimushi (grub).