Karin is a fit and athletic young kunoichi with fair skin and long black hair that reaches her waist. Her hairstyle features an asymmetrical fringe swept to the left side, complementing her sharp brown eyes. Her overall look reflects both agility and discipline, fitting her role within the Seven Samurai.

Before and during her initial encounter with Fena Houtman, Karin wears a red long-sleeved haori paired with a gray obi, black pants, and gray leggings that wrap around the arches of her feet. Like the other ninja in her group, she is barefoot during this period.

After joining Fena’s crew alongside the other samurai, Karin adopts a new outfit more suited for combat and utility. She dons a black ninja uniform with dark brown leather armor covering her chest and kote-style guards over her long sleeves, extending to her wrists and ring fingers. Her pants are equipped with two holster cartridge belts for ammunition, while her pistols are stored in holsters strapped to each leg. An additional ammo belt is fastened around her right thigh, and she wears protective leg guards on the lower half of her trousers.

Uniquely among her group, Karin wears belts around her waist instead of the red bows used by the other samurai, and she is the only one to wear black tabi footwear, a traditional ninja style that separates the big toe from the others while the others wear boots. She also stands out as the only member who does not wear a samurai helmet or men-yoroi (facial armor), emphasizing her distinct identity as the sole female in the group.

Karin’s primary weapons include a pair of pistols and a tanegashima musket rifle, which she carries strapped to her back.

Karin’s final character design retains much of her original appearance from the initial announcement, with several subtle yet noticeable changes. Her chest armor and kote-style arm guards are now tinted fuchsia, while her ammunition belts have shifted from yellow to red. Her eyebrows appear slightly smaller and shorter compared to the earlier design. Her black tabi footwear features gray accents on the toes, heels, and soles, with the arches of her feet covered by the lower portions of her pants.

Her casual outfit also underwent changes. The red haori she previously wore is now magenta, and her black pants have been replaced with red ones decorated with five buttons. Unlike some of her comrades who go barefoot or wear sandals, Karin now wears small black boots as part of her casual attire, with dark magenta-tinted quarter heels. Despite this, it is implied that she sleeps barefoot. Additionally, she is shown to have a faint blush on her cheeks, a trait she shares with Fena.

Karin remains the only member of the Seven Samurai not seen wearing a samurai helmet, and it is unknown what her design would look like if she were to don one.

As the only female member of the Seven Samurai, Karin stands out for her assertive and headstrong nature. She does not tolerate foolish behavior and often takes charge with confidence. Despite this commanding presence, she has a playful and passionate side, especially when it comes to her interests. Karin has a strong fascination with technology, weapons, and machinery particularly her firearms and is known to become highly enthusiastic or animated when discussing them.

Karin is energetic and outspoken, often geeking out over historical or mechanical subjects, revealing a more lighthearted aspect of her personality. Though she may come off as feisty and short-tempered, especially when irritated or teased, she is ultimately caring and loyal to her comrades. Her spirited and tomboyish personality sharply contrasts with Fena’s more gentle and traditionally feminine traits, yet the two share a close friendship.

According to her voice actress in an interview on the official Japanese website, Karin was intended to be a cool yet humorous character who casually interacts with the crew, showing a wide range of expressive reactions throughout the series. She also demonstrates a strong sense of camaraderie, having joined Fena’s crew with full devotion to their shared journey. During their visit to Bar-Baral, Karin reveals a childlike excitement when encountering rare or valuable items, such as yakusugi cedar and a rhinoceros horn, further highlighting her quirky enthusiasm.

The name Karin (花梨) commonly means “Chinese quince.” When broken down into its individual kanji, 花 (ka) translates to “flower” or “blossom,” and 梨 (rin) means “pear.” Together, the name reflects both botanical imagery and a gentle, natural elegance.