Mai Himuro is a classmate of protagonist Yuu Nagami and secretly works as a professional light novel author under the pen name Enryuu Homura. She is noted for her academic standing and physical traits, featuring blue eyes, dark red neck-length hair, a height of 1.64 meters, and measurements of 89-59-87.

Having established her writing career prior to the series' events, Mai holds deep admiration for works published under the name Chikai Towano, unaware this identity serves as a proxy for Yuu and his sister Suzuka Nagami. After learning of Yuu's public association with the Towano name, she initiates direct contact to study his creative process, positioning herself as both peer and dedicated fan. Her interactions frequently involve weaving into his personal life under the pretense of researching his methodology, extending to covert observation and intelligence-gathering about his routines.

During exchanges with Yuu, she displays a covertly imaginative nature that contrasts her outwardly composed demeanor. Mai deliberately requests Yuu address her by her first name to foster personal rapport, persisting despite his initial reluctance. Her narrative role involves compounding professional complications around Yuu's authorial deception and escalating interpersonal tensions through her persistent presence.