Makoto Ariga, known as Mako, is a transgender girl who begins as a sixth-grade classmate of Shuichi Nitori and Yoshino Takatsuki, though in a separate class. Assigned male at birth, she identifies as female and shares Shuichi's interest in feminine clothing and gender expression, forming the foundation of their close bond. She possesses a round face and body with a feminine appearance, medium brown hair in a bowl cut, freckles, and distinctive round glasses, which she feels hinder her ability to appear as cute as Shuichi when presenting female.

Her personality blends maturity and perceptiveness with deep insecurity. Makoto often offers calm, objective advice and acts as an observant listener, fostering positive peer relationships. Yet she struggles with persistent self-doubt, frequently comparing herself unfavorably to Shuichi and believing her physical appearance—especially her freckles and glasses—prevents her from being seen as an attractive girl. This lack of confidence causes hesitation to present publicly as female, though she privately wears dresses and feminine attire outside school, where the male uniform is required. Her self-worth issues are compounded by a belief that her desire to transition may stem partly from social attraction to boys, a motivation distinct from Shuichi's experience.

A pivotal development occurs during the school cultural festival when Makoto is cast as Juliet in a gender-nonconforming adaptation of *Romeo and Juliet*. Initially apprehensive, she reluctantly accepts. Despite freezing during her opening lines, she ultimately delivers a passionate performance, particularly in Juliet's death scene. This becomes a transformative display of confidence, culminating in a bouquet presentation from Saori (playing Romeo) and a dismissive reaction from her mother, who misinterpreted the scene as comedic.

Makoto's relationship with Shuichi is central. They bond over shared gender exploration, discussing feminine interests and trying on clothing together. Shuichi counters Makoto's self-criticism, emphasizing her compassionate personality over appearance. An only child, Makoto's parents run a bakery; their views on her gender identity remain largely unexplored beyond her mother's reaction to the play.

Across the series, Makoto's journey reflects ongoing challenges with self-acceptance and social transition. The manga depicts her as a transgender girl who eventually comes out to her mother in high school, while the anime presents a more ambiguous portrayal, sometimes framing her as a crossdressing boy. Her story involves navigating puberty, societal expectations, and identity complexities, with her transition unresolved.