Makeru Yadano attends Itan Private High School as a classmate of Shoko Komi during their first year. She stands approximately 156 cm tall with pastel pink hair typically styled in low twin tails and straight bangs. Her vision requires glasses occasionally. Physical records note a sitting height of 87 cm, grip strength of 18 kg, body flexibility of 45 cm, side-stepping at 42 times, sit-ups at 21 repetitions, and a handball throw of 5 meters. Her second-year 50-meter dash time is 7.88 seconds, and her weight fluctuates between 51.7 kg and 53.8 kg. Driven by an intense competitiveness and aversion to losing—reflected in her name's meaning—Yadano declares herself Komi's rival in academics, physical tests, and school events, though Komi rarely acknowledges this. Defeat triggers exaggerated reactions, tantrums, or claims of ties. This stems from insecurity over her "commoner" status versus Komi's "goddess" image, yet she values perseverance. She has an older brother, Katsuki Yadano, engaging in sibling rivalry. Academically, she excels in science and social studies but ranks poorly overall, peaking at 108th in summer term-end tests. She participates in the library committee (first year), assists at a local shop during summer break (second year), operates a Benugit Supopo grill booth at the cultural festival, and becomes president of the track and field club in her third year. Her development unfolds through recurring failures. Early one-sided challenges during fitness tests highlight Komi's superiority. A pivotal moment occurs during the third-year sports festival relay: after narrowly losing to Komi, Yadano's emotional outburst reveals her habit of masking genuine disappointment with comical overreactions to avoid pity. This vulnerability prompts Komi to finally recognize her as a legitimate rival, shifting their dynamic toward mutual respect. Relationships include an unofficial fan club led by Chiarai Shigeo, drawn to her dramatic persistence. Classmates perceive her as popular despite her self-deprecating "humble villager" label. Interactions beyond rivalry reveal hidden depths like adept clothing selection skills and a fondness for katsudon.