TV-Series
Description
Kapuru-kun, also known by the English name Cappy and the Japanese name Kaburu-kun, is a young hamster from the Hamtaro series with a white and brown coat. He is most recognizable for his constant accessory, a green swimming cap, though he has a deep passion for all kinds of headwear and is always searching for new and unusual things to put on his head. His most common alternative to the swimming cap is a giant red saucepan, which he also uses as a hiding place. His name in Japanese, Kaburu, directly refers to this defining characteristic, as it means to put something on one's head.

In terms of personality, Kapuru-kun is naturally shy and hesitant, but this timidity is paired with a persistent curiosity for unconventional objects to wear as hats. He lives with his human owners, a brother and sister named Kip and Sue. While he loves his home, he does not enjoy being spoiled and shows a desire for more independence. This motivation leads him to greatly admire Boss, a fellow Ham-Ham who lives as a field hamster, viewing him as a model of self-reliance and freedom. This admiration is a key part of his character, and in one episode, his desire to be more like Boss leads him to run away from home to live with him, only to return after learning about the hardships of independent life.

His role in the story is primarily as a supporting friend among the Ham-Hams, with several important relationships defining his journey. His closest friend is Stucky, with whom he shares a playful and energetic bond. They are often seen together engaging in games like hide-and-seek, and their relationship has elements of a friendly rivalry. Another significant friendship develops in the video game Hamtaro: Ham-Ham Heartbreak. In this story, the antagonist Spat steals a special acorn hat from a character named Seedric and gives it to Kapuru-kun. Although he is initially reluctant to return it, he eventually empathizes with Seedric's loss and personally returns the hat, leading to a strong friendship based on their mutual love for headwear.

Kapuru-kun is one of the youngest and smallest of the Ham-Hams. Officially, his height is listed as 7.7 centimeters, though in some media he is portrayed as being even shorter, with only the tiny Penelope being smaller than him. He very rarely removes his signature green swimming cap. One of the few times he does so is to use it as a fan to help cool down a sick Laura, or to replace it temporarily with a seashell during a trip to the beach. He shares his birthday, August 6th, with the series' main character, Hamtaro.