Pimmy, known as Koma in the original Japanese version, is a white cat distinguished by black markings adorned with white dots, pink ears, and facial markings resembling freckles. She remains the youngest member of the group, consistently portrayed as a kitten across all media. Her owner operates a local bathhouse, a recurring setting in her stories.

Embodying a playful and curious nature, Pimmy approaches life with wonder as she learns about feline behavior and life itself. She enjoys being treated as a younger sibling figure within the group, receiving guidance from the older characters. This dynamic features prominently in early OVAs like *Tama & Friends: Third Street Story*, where she is the sole female character among Tama's core companions. Her characterization evolves in later series such as *Tama of Third Street: Do You Know My Tama?*, revealing both tomboyish energy and traditionally girlish traits, forming a contrast with the more ladylike Momo.

A significant background event involves Pimmy running away from home after being reprimanded by her owner. Depicted in a dedicated episode, this experience leads her to understand the challenges of independence and the value of her existing home and relationships, prompting her voluntary return. Her interpersonal bonds include a close, sibling-like relationship with the stray cat Nora, noted in *Uchitama?! Have you seen my Tama?*, where their dynamic shows her gentle nature complementing his brooding personality. The freckle-like markings on her face are frequently emphasized across adaptations, visually reinforcing her status as the group's youngest member.