Ramurin Makiba is a pink anthropomorphic sheep distinguished by droopy dark pink ears and a forehead tuft. Her appearance evolves across the series, beginning with a red bow head accessory, a white short-sleeved shirt under a magenta jumpsuit featuring a gold zipper, and red shoes with white socks. Later outfits include a pink bandana, a plain white t-shirt beneath a fuchsia sleeveless jacket with a yellow hood, light blue shorts, and red shoes displaying white and yellow details. Another ensemble features an orange long-sleeved top paired with a yellow shirt bearing a magenta "R," worn over a navy skirt and lighter shorts. Her final outfit before departure consists of a cream-colored top, a pale pink cardigan, aqua bloomers, and pink Mary-Jane shoes adorned with white thighs and goldenrod stripes.

Personality-wise, Ramurin is characterized as reliable and observant, frequently detecting suspicious behavior with her catchphrases "Suspicious..." or "How fishy..." She exhibits a tomboy demeanor and rarely makes mistakes, contrasting characters prone to forgetting promises or mishandling situations. She is not a fast runner and harbors a fear of ghosts. Her interests include drawing and painting as hobbies, and she enjoys sports like sumo and judo. Pudding is her favorite food.

Residing on Challenge Island, Ramurin attends Challenge Kindergarten. Her family operates a ranch, reflected in her surname "Makiba" meaning "ranch." She is one of two main characters without siblings, alongside Mimirin. Her father is a painter, and she aspires to follow this profession. She shares close friendships with Shimajiro Shimano, Mimirin Midorihara (her childhood friend), Torippii Sorano, and Marurin Sasaki. Before leaving, she gave Mimirin her favorite ribbon as a keepsake.

Her story concludes in the *Shimajiro Hesoka* (2012) series finale, where she permanently departs Challenge Island with her family to emigrate to France. This exit marked her retirement from the franchise, after which she was replaced by Nyakkii. Her final episode is titled "Goodbye, Ramurin."

Additional background notes confirm her birthday is March 3, aligning with the Japanese holiday "Ohinamatsuri" (Girls' Day), her zodiac sign is Pisces, and her blood type is AB.