TV-Series
Description
Mafuyu Shiina is the treasurer of Hekiyou Academy's 32nd Student Council and the younger sister of Minatsu Shiina. She acts as a bridge between Minatsu and their mother following a family rift. Exposure to Minatsu's negative views about men during middle school led Mafuyu to attend an all-girls school, resulting in severe androphobia causing physical discomfort if touched by males. Her name, incorporating the characters for "true" (真) and "winter" (冬), reflects a seasonal motif.

She possesses long blonde hair reaching her waist and dark blue eyes, frequently carrying a pink handheld gaming console resembling a PlayStation Portable. Her birthday is February 22, and she has blood type A. She prefers hamburgers without pickles and dislikes fish with many bones.

Initially appearing shy, sickly, and passive, Mafuyu reveals hidden facets once comfortable. She is an avid gamer specializing in RPGs and operates the popular BL website "Internal Organs Explode," where she writes and sells boy's love fiction. Her fujoshi tendencies manifest openly as she creates BL scenarios involving council members, notably pairing Ken Sugisaki with a fictional boy named Yoshiki Nakameguro—who later materializes as a real transfer student. Despite her reserved exterior, she voices mature opinions and demonstrates unexpected physical assertiveness, such as striking a boy who mocked Ken.

Her background significantly intertwines with Ken Sugisaki. Before joining the council, she interacted with him online under the alias "Yuki" while he used "Key." She trained Ken through unconventional methods like applying makeup or sending him to cafés with stern waitresses, inadvertently shaping his later shameless personality. Their first physical meeting occurred when she helped him during a fainting spell caused by overwork, overcoming her fear of men. This encounter symbolized "true strength" for Ken.

As treasurer, Mafuyu rarely performs duties during meetings, instead proposing ideas related to gaming or BL. She initially struggled socially in her class, leading Ken to suspect bullying. Contrary to this, she was unknowingly idolized by classmates who conducted quizzes about her and organized "stalking missions" for her protection. The entire class once defended her during a confrontation involving Haro Akimine.

Her development shows growing comfort with Ken, culminating in her being the first council member to confess romantic feelings. She clarifies she prioritizes preserving the council's atmosphere over pursuing a relationship, an admission causing Ken visible distress due to his complex history. She later states she would choose Ken over her sister if forced. Her journey reflects the winter motif, transitioning from withdrawn to revealing warmth and resilience.

Outside the main series, Mafuyu appears in the "Gamers!" short story collection as the "Masked Gamer" who influenced fifth-grader Karen Tendō's interest in video games.