Gentle, brave and kind, James has been robbed of his childhood by his cruel aunts. He blossoms on the peach journey — becoming the natural leader of the insect group through his kindness and resourcefulness rather than through force.
The two aunts are Dahl's comic grotesques — Spiker is thin and bony, Sponge is fat and damp. Both are selfish, lazy and actively cruel to James. They represent everything adults should not be: self-serving, loveless and exploitative of the children in their care.
Boastful, cheerful and brave. The Centipede causes trouble but also saves the group at key moments. He loves to sing songs about himself.
Contrary to most people's expectations of spiders, Miss Spider is gentle, kind and creative. She spins and weaves throughout the journey and treats James warmly.
Pessimistic and always predicting disaster, but genuinely helpful in a crisis. His gloom provides comic contrast with the Centipede's optimism.