Kanchome is a mamodo, a supernatural child from another world who participates in a battle to determine the ruler of his realm. He is approximately the same age as the series' main character, Zatch, and is distinguished by a very unusual appearance. Kanchome has large, protruding eyes, a mouth shaped like a duck's bill, and a distinctive cone-shaped hairstyle. He typically wears a blanket sleeper, and one of its pockets is a seemingly endless repository for candy.

Personality-wise, Kanchome is primarily childish, lazy, and prone to abrasive behavior. He often resorts to crying and whining like a baby to get his way, and he is easily frightened, showing particular fear towards more intimidating mamodo like Brago. His major weakness is his insatiable love for sweets; despite having a pocket full of candy, he cannot resist pursuing any he finds lying around. This compulsion has led him into trouble on multiple occasions, including following a truck full of candy to Spain where he ended up in a traveling circus, and later being tricked onto a ship headed for Antarctica. Beneath this cowardly and gluttonous exterior, however, Kanchome occasionally displays surprising perceptiveness and a deep-seated determination to protect his friends when they are in genuine danger.

Kanchome's role in the story is closely tied to his human bookkeeper partner, the internationally famous Italian actor and singer Parco Folgore. Folgore is a flamboyant and melodramatic celebrity known for his terrible acting and hit songs, yet he possesses a hidden depth and a strong sense of loyalty. The duo are initially introduced as rivals to the main characters but quickly become comedic and dependable allies. Their relationship is the core of Kanchome's character; Folgore acts as a mentor and a source of unwavering encouragement, often enduring the brunt of enemy attacks to protect his small partner. In turn, Kanchome's unique abilities are vital to their shared survival. A running gag is that when Folgore is knocked down, Kanchome sings Folgore's theme song, "Muteki Folgore" (Invincible Folgore), which inexplicably revives him and allows him to continue fighting. Kanchome also forms key relationships with other mamodo, particularly Zatch and Kido. He has felt guilt over his perceived weakness, such as when he blamed himself for Kido's book being burned during a battle against a powerful ancient mamodo.

Throughout the series, Kanchome undergoes significant development. Initially portrayed as one of the weakest and most useless fighters, he often relied on trickery and luck to win battles, frequently using his shrinking spell, Koporuku, to sneak up and burn an opponent's spellbook with a match. As the battle for king progresses, Kanchome receives special training to awaken his hidden potential. This results in a dramatic increase in power, allowing him to learn new spells and easily defeat opponents who once seemed far stronger than him. However, this newfound strength comes with a monstrous drawback; in gaining what he wanted, Kanchome risks losing himself and descending into a terrifying, uncontrollable madness that his partner Folgore must help him overcome.

Kanchome's notable abilities are almost entirely based on transformation and illusion, reflecting his crafty and deceptive nature. His spells, which are inscribed in his yellow spellbook, focus on trickery rather than direct force. His first spell, Poruku, allows him to transform into any object he can imagine, though he typically only gains its shape and not its inherent abilities. Koporuku shrinks him to a miniature size. Dika Poruku creates a giant illusion of himself that appears invincible, as enemy attacks seem to pass through it harmlessly. In the sequel series, he gains a new spell, Mo Poruku, which transforms him into a large disembodied head that can engulf opponents and physically transform their bodies into copies of his own form. As he grows stronger, Kanchome learns more potent illusion-based spells like Fou Supuporuku, which can trick an enemy into canceling their own attack, and Miriaru Poruku, which fools an opponent's mind into believing he is using their own spell against them, causing their body to take real damage. His ultimate technique, Shin Poruku, is his most powerful ability, creating an illusory world where he can completely control the hearts and minds of his enemies, trapping them in a reality of his making with no hope of escape.