Ichika Nakano is the eldest of the quintuplets and an aspiring actress (ENFP) who calls Futaro 'Futaro-kun.' She has been proactive and playful since childhood, but after falling in love with Futaro, she wavers between her feelings and her bond with her sisters. She once lost Futaro's trust by disguising herself as Miku to interfere with their relationship, but she reflected on her actions while helping Miku out of guilt. Despite this, she couldn't give up her feelings and impulsively kissed him in the park after the Sunrise Festival. Even now, as her acting work kept her from the festival, she waits for his choice, wondering where his heart lies. She often refers to herself as 'Big Sister.' She is a responsible eldest daughter with a short haircut and is very popular.

The second daughter, Nino Nakano, has a particularly strong attachment to her sisters. Since she valued the five of them being together above all else, she was initially wary of Futaro and pushed him away when he suddenly entered their lives. However, watching him work sincerely for her and her sisters, her hostility gradually turned into affection. Once she realized her love, she became proactive enough to confess directly without hiding or mincing words. While she wants Futaro for herself more than anyone, she eventually matures by accepting that her sisters' happiness is as precious as her own love. Her MBTI is ESFJ. When calling Futaro, she uses 'Uesugi' or the nickname 'Fu-kun.'

Miku Nakano is the third of the quintuplets, possessing a quiet, shy personality that rarely shows emotion. She loves Sengoku period warlords but used to hide this hobby out of embarrassment, and she didn't open her heart to Futaro easily at first. However, as Futaro took her interests seriously and helped her study, she grew fond of him and was the first to realize her love. Since then, she has grown by working hard at cooking and studying to become someone worthy of him. Though clumsy and passive in love, her feelings are deep and unwavering, and she gains confidence and courage through her emotions for Futaro. Her MBTI is INFP. She lacked confidence, but after meeting Futaro, she realized her potential and recovered her self-esteem. She calls him 'Futaro.' She is shy but cares for Futaro more than anyone. She is kind and warm.

Yotsuba Nakano is the fourth sister, possessing a bright, cheerful, and warm personality that finds it hard to refuse any request. She is athletic and always helps others first, but she tends to put her own happiness last due to the guilt she feels over her past actions causing the sisters to transfer schools together. In truth, she is the girl who met Futaro in Kyoto five years ago and promised to study hard so they could become special people. She recognized him the moment they reunited but hid her feelings for the sake of her sisters. While she has loved Futaro for a long time, she tried to support the other sisters' love. She calls him 'Uesugi-san.' Her MBTI can be assumed to be ENFP.

Itsuki Nakano is the youngest of the quintuplets, a hard worker who is diligent, responsible, and somewhat stiff. She deeply respects her late mother and aims to become a teacher like her, valuing her sisters as family more than anyone. She initially clashed with Futaro frequently, but as she learned of his sincerity and sense of responsibility, she became one of his most reliable supporters. She even tried to connect Yotsuba and Futaro, knowing their past. She realizes her feelings for Futaro much later than the other sisters and eventually accepts her heart quietly. She mainly calls him 'Uesugi-kun.' Her MBTI can be assumed to be ISTJ.