Miku Nakano is the third eldest of the Nakano quintuplets and one of the main characters of The Quintessential Quintuplets. Initially standing out as the quietest and most reserved of her sisters. Miku has medium-length prominent strand of hair or looped side-swept bang that hangs over and obscures the right side of her face while leaving a clear gap for her right eye to peek through, reddish-brown hair, dark-blue eyes, and her signature blue headphones, which she usually wears around her neck. She generally dresses more simply than her sisters, favoring sweaters, her school uniform, and a relatively understated style. Her biggest strengths are her intelligence, knowledge of Japanese history, and ability to disguise herself as her sisters. She is especially knowledgeable about the generals of Japan’s Sengoku period, a hobby she initially keeps secret because she’s embarrassed about it. She is considered the smartest of the quintuplets, with Social Studies being her strongest subject, although she struggles with physical activities and cooking. Miku is shy, quiet, reserved, and initially has very low self-confidence, often underestimating herself compared with her sisters. However, she is also kind, honest, determined, and surprisingly straightforward when she needs to stand up for herself or someone she cares about. Throughout the story, she gradually becomes more confident, learns to express her feelings, and works hard to improve herself, making her character development one of the major parts of the series. Miku grew up alongside her four identical sisters—Ichika, Nino, Yotsuba, and Itsuki—and was particularly affected by the changes in their family after their mother’s death. Her quiet nature and low self-esteem caused her to distance herself from others. She eventually becomes more open about her passion for history and her feelings, while also learning that she can develop her own identity rather than simply comparing herself to her sisters.

Nino grew up extremely close to her four sisters and strongly believed in their mother’s philosophy that the five of them should always remain together. After their mother’s death, the sisters gradually developed different personalities, and Nino became especially protective of their bond. Nino Nakano is the second eldest of the Nakano quintuplets and one of the main characters in The Quintessential Quintuplets. She is extremely protective of her sisters. Nino has long straight reddish-pink hair, very long hair, flowing past her shoulders down to her waist or hips. Her bangs are blunt, square-cut bangs that hang straight across her eyebrows, dark-blue eyes, and is recognizable by her twin butterfly-shaped ribbons. She is also particularly fashionable among the sisters and frequently pays attention to her clothes, accessories, nails, and overall appearance. Her biggest ability is cooking—she is the best cook among the quintuplets and regularly prepares meals, sweets, and other food for her family. She is also socially confident and has many friends, while English is her strongest academic subject. Nino is outgoing, blunt, confident, stubborn, and sharp-tongued, often giving her a classic tsundere personality. Beneath her aggressive exterior, however, she is extremely caring and protective of her sisters, often taking on a mother-like role by cooking for them and looking after their well-being.