Bubble is one of the main characters of The Amazing Digital Circus. He's a living bubble that seems subservient and friendly to Caine, living inside his hat until called upon. He can be popped and be returned into Caine's top hat.Bubble, as his name suggests, is a large round bubble with sharp, deadly teeth constantly displaying a vacant expression. Being a bubble, most of his body is shiny and transparent. His eyes are black dots. When it is necessary, Bubble can form a long, red tongue.