Kasumi (香澄 Kasumi) is the ex-girlfriend of Taichi Mashima who got together during a difficult time in Junior High School as Taichi had lost his passion for Karuta, but Kasumi shared her love for him and they started dating. However, this relationship did not last very long.
After meeting Chihaya Ayase again in High School and finding his passion for Karuta again, there was no place for Kasumi anymore and Taichi breaks up with her over the phone in a short and dry exchange by saying "We've broken up" in Episode 17/Chapter 29.
Kasumi is a slim woman with neck-length dark brown hair and dark brown eyes. She has been seen casually dressed with some makeup put on.
Kasumi has gotten together with Taichi during Junior High School. But, in high school, Taichi broke up with her again for the sake of Karuta and his love for Chihaya Ayase.
Kasumi has met Chihaya only shortly in Episode 4/Chapter 7 at the train station where Kasumi was waiting for Taichi. When he and Chihaya arrived, she greeting Taichi while Chihaya all of a sudden spurted out a challenge to Taichi that if she wins the next tournament to get into Class A, Taichi had to open up a Karuta Club with her. Kasumi was a little stumbled by the strange women she never met and immediately asked Taichi who that was.
- The name Kasumi means "fragrance, fragrant" (香) (ka) and "clear, pure" (澄) (sumi).