In the anime film Rudolf the Black Cat, Bucchi is a stray cat living on the streets of Tokyo who becomes one of the protagonist Rudolf’s first and most important friends. He is a hyperactive and talkative tabby cat, known for his nervous energy and easily distracted nature. Some descriptions characterize him as a calico, while others note his behavior suggests a mild case of attention deficit disorder, making him a high-spirited and sometimes erratic companion.

Bucchi’s personality is a mix of street smarts and comic relief. He is well-informed about the dangers and gossip of his neighborhood, acting as a scrappy source of information for the newly arrived Rudolf. For instance, he is the one who tells Rudolf about the feared local dog named Devil and reveals that the gruff Gottalot was once known as the Junk Tiger. Despite his knowledge, Bucchi is easily distracted, particularly by romance. He is known for becoming instantly enamored with attractive female cats, often losing his train of thought or cutting a story short to pursue a beautiful Siamese cat he spots on the street. This romantic side of his character is further developed as he eventually starts dating one of these cats, sharing an accidental kiss with her in a moment that parallels the famous spaghetti scene from Lady and the Tramp.

His role in the story is primarily as a loyal ally and a source of comic energy. He readily offers to let Rudolf hang around his house and helps the lost kitten navigate the complex social and physical landscape of the city alongside the more experienced Gottalot. Bucchi’s defining quirk is his habit of mimicking martial arts moves, often punctuating his actions and excited speech with a sharp cry of Hyah. This habit, combined with his boundless energy, makes him a memorable and lively presence throughout the film. Through his friendship with Rudolf, Bucchi also learns lessons about appropriate behavior, adding a small but clear arc of personal growth to his character.