Koma, a white cat from "Tama and Friends," displays distinctive black circular markings above her eyes and pink ears. Her owners run a public bathhouse on Third Street, fostering her unusual comfort with water. As the group's youngest member, she exhibits kitten-like curiosity, playfulness, and a habit of chasing moving objects while learning about life and her feline identity.

She frequently accompanies Momo during activities or searches and admires Tora's adventurous spirit, looking up to him despite their mutual teasing. Koma shares a close, sibling-like bond with Nora, often pulling the aloof cat into group endeavors. Occasionally, she assists patrons at her family's bathhouse.

Impulsive actions define key story moments, such as eating from a stranger's dog bowl uninvited, forcing her and Momo to flee an angry dog. Koma also faces vulnerability, running away after an owner's scolding. This experience teaches her the difficulty of finding a new home, deepening her appreciation for her family before she returns.

The 2016-2018 series "Uchi no Tama Shirimasen ka?" reimagines Koma as a human with animal traits: white hair styled around her head, darker hair sections above her eyes, pink inner ears, violet eyes, and black-and-white attire, maintaining her energetic youthfulness.

Her franchise presence extends to merchandise like plush toys and acrylic memo stands.