There is no major fictional character named "Kyouka Mashiba." It is likely you are referring to Ryo Mashiba from the boxing series Hajime no Ippo Kyoka Izumi Bungo Stray Dogs
For those who only watched the 2015 anime, you have seen only the prologue of Kyouka’s story. In the light novels (volumes 2-6), her character arcs dramatically deepen.
Despite his relatively obscure status, Kyouka Mashiba's contributions to Japanese literature have had a lasting impact on the country's cultural landscape. His innovative storytelling and thematic preoccupations have influenced generations of writers, from the likes of Jun'ichirō Tanizaki to Haruki Murakami. Moreover, Mashiba's works have been instrumental in shaping the contours of Japanese modernism, providing a unique perspective on the country's tumultuous transition from a traditional to a modern society.