TV-Series
Description
Karupin is a Himalayan cat belonging to the Echizen family, making his home in the household where the tennis prodigy Ryoma lives. His breed is characterized by a plush, slightly stout build, with brown and white fur and striking blue eyes. He has a birthday given as December 24th, which is often noted in supplementary material about the series. As a resident of the Echizen home, he is a constant and beloved presence, particularly known for being the closest companion to Ryoma.

In terms of personality, Karupin is frequently depicted as a calm and easygoing cat, often found sleeping or lazily roaming around the house. He spends a great deal of time in Ryoma's bedroom, often sleeping alongside him in a similar posture. However, beneath this placid exterior lies a core of intelligence and notable mischievousness. This cleverness is shown through his awareness of his owner's belongings, such as when he realized his favorite toy had been accidentally packed away and proceeded to follow Ryoma to school. His motivations are primarily those of a curious and attached animal: he seeks comfort, play, and proximity to the people he likes, especially Ryoma. He is also motivated by simple feline pleasures, such as playing with toys or enjoying kitty snacks.

Karupin's primary role in the story is to serve as a significant emotional anchor for Ryoma, revealing a softer and more vulnerable side to the otherwise confident and sometimes aloof main character. The cat's actions often drive minor but character-revealing plot points. For instance, when Karupin wandered away from home and followed Ryoma to school, it caused Ryoma great distress, leading him to search frantically for the cat and neglect his tennis training. In another instance, Karupin hid inside Ryoma's bags and accompanied him all the way to America for the USA Open, demonstrating the depth of their bond and the cat's daring nature. Through these events, Karupin humanizes Ryoma, showing that his dedication to tennis is balanced by a deep, genuine care for his pet.

His key relationships are central to his depiction. The most significant relationship is, without question, with Ryoma Echizen. Ryoma deeply loves Karupin above nearly all else, a sentiment the cat wholeheartedly returns despite the trouble he sometimes causes. Ryoma is often seen carrying Karupin, has a photograph of him in his bag, and even says his name in his sleep. Karupin acts as a living alarm clock, using a distinctive jumping motion to wake Ryoma when he is being particularly stubborn about getting out of bed. The two are rarely apart when Ryoma is at home, and any mischief on Karupin's part is always forgiven.

The relationship with Nanjiroh Echizen, Ryoma's father, is notably antagonistic. The two do not get along and are frequently seen fighting or otherwise expressing mutual annoyance. Karupin is known to bite, scratch, or destroy Nanjiroh's magazines, particularly his adult-oriented ones, showing a clear lack of fondness for the older man.

In contrast, Karupin shares a much warmer bond with Nanako Meino, Ryoma's cousin. She cares for Karupin when Ryoma is at school or away at tournaments, and the cat seems to love her in return. An unexpected but recurring relationship is with Kaoru Kaido, a fellow member of the Seigaku tennis team. Despite Kaido's intimidating demeanor and his nickname "the Viper," Karupin seems to enjoy his company and wants to play with him whenever they meet. Kaido, in turn, shows a gentle side in these interactions and is visibly disappointed when the cat has to leave. On one occasion, Kaido was also among the Seigaku regulars who found and returned Karupin after he had gone missing.

Regarding development, Karupin does not undergo a significant personal arc or change in personality throughout the story. His role remains consistent as a cherished pet and a catalyst for showing Ryoma's emotional depth. His consistent loyalty, playful mischief, and the simple routine of his life at the Echizen household are his primary characteristics. He is a static but important figure.

Karupin has a few notable abilities beyond those of an ordinary cat. He is exceptionally clever, able to track Ryoma to school and hide in luggage for international travel. He has a special skill sometimes referred to as the "Backfoot Kitty Kick." He is also a surprisingly effective alarm clock, using his weight and jumping ability to jolt Ryoma awake, which is apparently more reliable than a conventional alarm. His strong reaction to play, particularly with a wiggling, snake-like toy, once led him to pounce and bite Nanjiroh's toe, demonstrating his focused hunting instincts.