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Due to Yotsuba's helpful personality, combined with her cheerful and bright traits, she is able to make a lot of friends. Yotsuba is sentimental towards familial feelings.
In Kyoto, she promised to study to lessen the load on her sisters and her mother.
Yotsuba calls Ichika as "Ichika." Yotsuba often cleans Ichika's room. Yotsuba tries to cheer up Ichika. Ichika stole candies and stickers from Yotsuba in the past. Ichika also made friends with someone Yotsuba wanted to befriend with. Yotsuba is the one who would usually clean her room as it is usually in a messy state. Yotsuba looks up to Ichika as the elder sister of the family, expressing her concern for Ichika whenever she is upset and would not hesitate to help her get better.
Ichika used to brush Yotsuba's teeth when they're kid.
Nino is protective of Yotsuba. Nino always brought bandages with her because someone in her family got injured all the time.
Yotsuba understands Miku's feeling with only the slightest signs, implying her awareness & care towards Miku's well-being.
Itsuki consoles Yotsuba by showing her Fuutarou's notes praising Yotsuba.Itsuki is the first to learn of Yotsuba's past with Fuutarou, and is asked to disguise herself as Yotsuba from 5 years ago. While Itsuki believes that Yotsuba deserves a chance with Fuutarou, Yotsuba refutes it, feeling undeserving of it and wanting to not be the only one who is "special" to him.
Yotsuba calls Fuutarou "Uesugi-san." Yotsuba's first impression of the new Fuutarou is "someone gloomy and doesn't have many friends." Fuutarou's first impressions of Yotsuba is that she is a simpleton.
Yotsuba is the only sister who accepts Fuutarou as a tutor early in the series. She happily cooperates with him to make her sisters acknowledge Fuutarou. Yotsuba is eager to be taught, and happy because the tutor is someone in the same grade. She wholly believes in his ability of teaching to a point she would reject the thought of another tutor. During their first date, Yotsuba realizes what she really wants, the smile/happiness of Fuutarou. Yotsuba's main reason to nominate Fuutarou as the class rep is to make people understand how nice Fuutarou is. Yotsuba declares that whoever Fuutarou likes, she will support him.
It is revealed that Yotsuba was the girl in Kyoto who saved Fuutarou from police, although he later ended up talking to another unidentified Nakano Quintuplet. This spurred her on to try to distinguish herself so there wouldn't be any more confusion.
Yotsuba has been in love with Fuutarou, however believes that she can't have a chance when three of the sisters have already been forward with him. She recognised him when she handed him his test when she transferred in, however was too embarrassed about her academic performance to bring up that they had met, or the mutual promise to study hard and be useful.
- ^ Manga Chapter 37 (p. 13).
- ^ Manga Chapter 88 (p. 13).
- ^ Manga Chapter 12 (p. 4).
- ^ Manga Chapter 2 (p. 11).
- ^ Manga Chapter 66 (p. 6).
- ^ Manga Chapter 66 (p. 8).
- ^ Manga Chapter 66 (p. 8).
- ^ Manga Chapter 45 (p. 14).
- ^ Manga Chapter 26 (p. 7).
- ^ Manga Chapter 31 (p. 12).
- ^ Manga Chapter 1 (p. 25)
- ^ Manga Chapter 1 (p. 28)
- ^ Manga Chapter 1 (p. 43-44)
- ^ Manga Chapter 2 (p. 6).
- ^ Manga Chapter 72 (p. 9).
- ^ Manga Chapter 72 (p. 15).
- ^ Manga Chapter 72 (p. 16-17).
- ^ Manga Chapter 87 (p. 19).
- ^ Manga Chapter 89 (p. 18).
- ^ Manga Chapter 88 (p. 21).
- ^ Manga Chapter 90 (p. 19).
- ^ Manga Chapter 88 (p. 15).
- ^ Manga Chapter 90 (p. 2).