Mr. Mole, known also as Leonard, is an anthropomorphic mole with brown fur and black eyes. He typically wears a sky blue cap and navy blue sunglasses. His primary interests involve excavating fossils and constructing underground tunnels, reflecting his natural subterranean inclinations. He maintains a friendship with Naoko Watanabe, who visits him during the episode "Mole Life" in season one. Naoko considers adopting aspects of his underground lifestyle as a potential solution to her personal challenges. His family consists of Leonard's Father and Leonard's Mother, both anthropomorphic moles. Leonard's Father wears glasses. Leonard's Mother also wears glasses and accessorizes with hair ribbons.