Fumika Kodama, also known as Katie Forester, appears across multiple installments of the media. As a child in Springdale, she attends Springdale Elementary School alongside classmates Nathan Adams, Edward Archer, and Barnaby Bernstein. Her appearance features black eyes and brown hair typically styled in a ponytail secured with a pink ribbon. She commonly wears a light yellow jacket with teal trimmings, multicolored buttons, and a pink heart detail over a black-and-white striped top, paired with blue shorts, dark grey socks, and black sneakers with white laces. Seasonal variations include a winter outfit with a light pink jacket and leggings, and rainy weather attire featuring a pink raincoat and black wellington boots. Her personality blends kindness, playfulness, and intelligence, making her popular among classmates. She occasionally displays unintentional insensitivity, such as frequently calling Nathan "average," though this often stems from yo-kai influence rather than malice. She remains largely oblivious to romantic attention, including Kyubi's persistent efforts to charm her. Fears include frogs, while she exhibits comfort with heights. Academic pressure from her mother's expectations is a noted concern. Within the narrative, she alternates between playable protagonist and supporting character. When chosen as the main character in the first two games, she discovers a pocket watch-styled yo-kai watch worn around her neck after encountering Whisper near Mt. Wildwood's sacred tree. This path follows her journey befriending yo-kai like Cadin and battling adversaries such as Buhu. If not selected, she occupies a secondary role within the friend group. Her gameplay mechanics grant her faster running speed compared to Nathan. A parallel universe scenario depicts her possessing the watch instead of Nathan, leading to divergent storylines where Whisper serves as her butler and Jibanyan manifests as Baddinyan. Yo-kai Watch 3 introduces her yo-kai transformation, Mee 2, playable in specific quests, enabling cross-dimensional travel between her world and Nathan's. Another yo-kai variant, Kamakiri On'na, appears in the Kuroi World. The Shadowside timeline, set 30 years later, shows her as an adult married to Nathan Adams, with whom she has two children: Summer and Tate. Her adult appearance retains the ponytail but uses a pink ribbon instead of the childhood bow, typically featuring a pink shirt, often with an apron. She expresses consistent maternal concern, particularly when Tate exhibits unusual behavior or Summer faces danger. Significant events include frequent inspiriting by yo-kai, requiring Nathan's intervention, such as Tattletell causing her to embarrass Nathan publicly or Dismarelda inducing sadness. During the Shadowside era, an Onimaro infection transforms her and Tate into Kaodeka Oni, leading to their temporary petrification by Summer. Her dynamic with Nathan evolves from childhood friendship to marriage, marked by his persistent attempts to impress her and eventual union. Relationships extend beyond Nathan, including friendships with Edward and Barnaby, and familial bonds with parents Rebecca and Jason Forester. As an adult, she interacts with her children and mother-in-law Lily Adams. Notable trivia includes her yo-kai watch's necklace design contrasting with wrist-worn variants, her appearance as the manga protagonist in "Yo-kai Watch: Wakuwaku Nyanderful Days," and her association with the Charming Tribe in mobile games.