Mako Saitō is the older sister in the Saitō sibling pair, sporting chest-length purple hair with distinctive bangs hanging over the right side of her face and greenish-yellow eyes. Her personality blends quietness with straightforwardness, sometimes revealing eccentricities like practicing alien languages with a hand puppet. A passionate idol otaku deeply immersed in anime and manga culture, Mako harbors a recurring dream of becoming a world-saving heroine, mirroring her friend Chiko Shinmoto's world-conquering ambition. She works part-time at a café while her educational background remains undefined. Despite her reserved nature, she enjoys notable popularity among peers for reasons unclear. Mako exhibits a pronounced brother complex, characterized by destructive sibling rivalry and resentment fueled by perceived parental favoritism toward her younger brother, Mao. Her surname Saitō uses the kanji for "simultaneous/alike" (斉) and "wisteria" (藤); her given name Mako carries potential meanings like "real child" (真子) or "truth child" (眞子).