Miku Nakano/Relationships

Miku is portrayed as the less sociable sister among the five. Despite that, Miku has a friend that calls her "Miku-chan", hinting a close friendship (as opposed to Nakano-san, or Miku-san).

Ichika Nakano
Miku pairs with Ichika for the Test of Courage. Ichika and Miku are close, as they often seen doing activities together compared with the other sister. They also trust each other a lot, and Miku even readily compromises her interest for Ichika's sake. Miku told Fuutarou about Ichika's movie.

Nino Nakano
Nino-Miku quarrel is first shown. Miku labels Nino as someone who is too stubborn. Ichika notes that Nino and Miku's dynamic is similar to cat and dog. Miku says that Fuutarou needs to use sincerity to deal with Nino. Nino's personality is a contrast to Miku's, and because to this they often quarrel with each other. Both of them doesn't hesitate to speak bluntly towards each other and even gives remarks that seems insulting. Even on normal occasions, Miku is at odds with Nino. Despite that, they're still close and care for each other. Miku reveals to Nino that she likes History and Sengoku Generals.

Yotsuba Nakano
Yotsuba said that the sisters know each other's thoughts just by expression, and she correctly guess Miku's feelings, indicating good relationship between the two.

Itsuki Nakano
Miku & Nino call Itsuki as "Itsuki." Itsuki reassures Miku about Fuutarou's circumstances, hinting her awareness and care towards Miku's feelings.

Fuutarou Uesugi
Miku calls Fuutarou "Fuutarou."

Fuutarou's first impressions of Miku is someone you can't get a read on.

Miku understands that Fuutarou sees the girls as student, not as girls.

Miku initially rejects Fuutarou as a tutor because she's expecting someone better. After Fuutarou found out her secret and appreciates it, Miku began to accept him, only to reject him again due to Fuutarou's lack of knowledge. He spent a lot of effort in studying, and later manages to successfully gain her approval. Fuutarou also motivates and inspire Miku to start studying, making her the first sister who accepts Fuutarou as a tutor.

After spending a lot of time with him, she would harbour strong feelings for Fuutarou, showing jealousy whenever another girl shows an interest in him, including her sisters. Miku willingly goes to a further store from her home just for a tiny chance of meeting Fuutarou.

Miku realizes why she likes Fuutarou, it's because of the warmth he emanates. Miku wants Fuutarou for herself, but she likes the six of them being together.

Classmates
A girl calls Miku as "Miku-chan."